The City & the City

Inspector Tyador Borlú of Besźel's Extreme Crime Squad arrives at Pocost Village on Kordvenna, where four teenagers have discovered a young woman's body beneath a wet mattress after seeing scavenging animals nearby. She is almost naked except for stockings and one high heel. Borlú questions Vilyem Barichi, one of the teenagers, who reports that a van had driven onto the grass near the skate park while it was still dark. Officers Shushkil and Briamiv moved the mattress while checking whether the woman was alive, potentially compromising evidence; Borlú later puts them on report.

Pathologist Stepen Shukman, assisted by Hamd Hamzinic, examines the body at the scene. He estimates she has been dead about twelve hours and says she was killed elsewhere. Her face is battered and cut along the left cheek and jaw, and there are wounds on her chest. Detective Bardo Naustin suspects she was a sex worker murdered by a client, but constable Lizbyet Corwi cautions against assuming that identification. She points to the victim's well-maintained brown hair and thick, earth-toned makeup, which differ from the appearance of many local street workers.

Borlú asks Naustin to question the teenagers with Ramira Yaszek and canvass local sex workers. Recalling Corwi's work on a previous case, he informally directs her to investigate Pocost Village and report to him, without arranging a formal secondment. After addressing reporters at the edge of the estate, Borlú briefly makes eye contact with an elderly woman in a foreign street, realizes he should not have seen her, and looks away. She looks away as well.

On his way back toward central Besźel, Borlú asks Corwi whether the body disposal might involve breach. She considers it unlikely because Pocost Village is a total Besźel area and the closest crosshatched streets lie hundreds of metres away, although the possibility is not conclusively eliminated. Borlú also handles other cases, including a domestic homicide, the death of Styelim during a burglary, and the racist murder of Avid Avid. Ramira Yaszek reports that Naustin struck the teenage witness Sergev during questioning. The teenagers' accounts agree, but it was one girl who noticed a grey van drive onto the grass, circle near the skate park, and leave quickly while it was still dark. She cannot identify its make, and other vehicles later visited the area.

Commissar Gadlem permits Borlú to continue devoting resources to the unidentified woman's murder. Corwi first questions local contacts and later drives Borlú through Kordvenna on a nighttime canvass. They show a cleaned-up photograph of the victim to local sex workers and young men associated with street crime. No one recognizes her or comes forward afterward. Despite limited resources, Borlú decides to circulate identification posters throughout Besźel's divisions.

In an autopsy-room encounter recounted after the canvass but placed on the preceding day, Shukman reports that the victim was approximately twenty-four or twenty-five and died of four narrow chest punctures, one piercing her heart. He believes an earlier blunt blow to the left side of her head may have stunned or incapacitated her. Small punctures on her scalp have an uncertain cause, and rust, abrasions, and marks consistent with dragging are present, mostly after death. There are no defensive wounds or signs of recent intercourse, leaving the initial sex-worker theory unverified. Borlú also reflects on Besźel's history of Jewish and Muslim coexistence and discrimination while observing Shukman's assistant Hamzinic. The chapter ends when Hamzinic appears about to speak but offers no further information.

Identification posters for the murdered woman have gone up across Besźel, including near Inspector Borlú's apartment on heavily crosshatched VulkovStrász. A railway belonging to the other city runs within metres of his window, but he must unsee the trains and their passengers. While walking toward Extreme Crime Squad headquarters, Borlú learns from Ramira Yaszek that police have found a van resembling the one described by a teenage witness.

The dirty, off-white Volkswagen stands unlocked in an alley that is itself crosshatched. Its cargo area contains rust-covered junk, nylon cord and stains that initially test as the victim's blood type; a definitive match follows by the next morning. Borlú infers from the rust on the victim and her failure to shield herself from the rubbish that she was unconscious or dead while being transported in the van. None of the debris looks convincing as a murder weapon, however, and the clutter creates a problem of excessive rather than insufficient trace evidence.

The van belongs to Mikyael Khurusch, a secondhand trader with convictions for assault, theft and buying sex. He says it was stolen three days earlier but admits that he did not report the theft to police. He cooperates with questioning and says he attended a Gamblers Anonymous meeting in Vyevus on the night in question, went to a bar afterward and left with a woman from the group. Seven of the eighteen group members corroborate his account; the woman is not identified, though others confirm her existence. A few of Khurusch's arm hairs found on the victim do not establish direct contact because he frequently used the vehicle. His secretary, Ljela Kitsov, confirms that he had complained about the missing van. Khurusch disowns the junk discovered inside it. Borlú is left without a verified killer or murder weapon, while Khurusch's small-scale trading business includes occasional journeys to Ul Qoma.

Two supposed identifications of the murdered woman collapse: the missing office assistant has merely left her job, while Rosyn 'The Pout' is found working and does not resemble the victim. Borlú continues to investigate who used Mikyael Khurusch's stolen van, but the few hairs linking Khurusch to the woman do not outweigh his corroborated account of the evening. On the Monday after the body's discovery, Borlú receives a poorly connected, anonymous call from a man in Ul Qoma. The caller says he knew the victim as Marya, the name she went by, and describes her as a foreigner who lived in Ul Qoma, moved among political radicals, and sought knowledge across both cities. He is frightened that her death might endanger himself and others.

The caller refuses to identify himself, dismisses Borlú's authority and criticizes the division between the cities. When Borlú asks how he learned of the death, the man says he saw the Besźel police identification poster and hangs up. Borlú regards this as information obtained through breach, rather than an ordinary cross-border telephone conversation. Although the caller may be telling the truth, Borlú fears that pursuing the lead openly could invalidate a later conviction and expose him to Breach's jurisdiction. He considers abandoning the case or destroying his notes, but does neither.

That night Borlú drinks, rereads his notes and concludes from the caller's language and attitude that he is probably a unificationist; this is Borlú's deduction, not a confirmed identification. He leaves Corwi a message presenting the search of unificationist groups as a speculative lead from the Dissident Unit and directs her to seek Shenvoi's help. He also leaves Taskin Cerush a request for advice about referring a case to the Oversight Committee and possibly Breach. Unable to sleep, Borlú deliberately looks at buildings and pedestrians in Ul Qoma and then into a passing foreign train, briefly meeting the eyes of some passengers. The chapter ends with his conscious violation of the normal practice of unseeing.

Borlú reflects on the distinct languages of Besźel and Ul Qoma, their common ancestry, and the uncertain history of the cities' separation. Corwi calls with a lead: a unificationist in Besźel recognizes the victim's photograph. At the Besźqoma Solidarity Front office on BudapestStrász, the investigators question Pall Drodin, whose group operates under constant police scrutiny and fears intervention by Breach.

Drodin says the woman called herself Byela Mar, a plausible Besź name that plays on an expression meaning nothing worth noting. About three years earlier, she had spent a couple of weeks using the group's library and questioning members about the cities' history. Although she initially seemed interested in their political work, Drodin concluded that she chiefly wanted information about Orciny, a supposed secret third city said in folklore to occupy gaps between Besźel and Ul Qoma. Drodin describes the woman as unnerving and potentially dangerous to his group, but he does not claim to have witnessed her breaching or to know that Orciny exists. He says she intended to move officially to Ul Qoma; he only heard, without confirmation, that she later might not have been allowed to return to Besźel.

Borlú takes Corwi to lunch in Ul Qomatown, an Ul Qoman expatriate district that belongs to Besźel. They consider whether the woman's apparent move to Ul Qoma and subsequent death in a total Besźel area indicate breach, while acknowledging that she might have crossed legally or remained in Besźel. Borlú argues that if breach occurred, the Oversight Committee should refer the investigation to Breach, and asks Corwi to establish the woman's identity through contacts in both cities. Taskin Cerush explains that the committee may take days to hear the request because of political and scheduling pressures, including the National Bloc's resistance to frequent invocations.

Late the following day, Corwi returns with a faxed file from Ul Qoma containing photographs of the victim alive and her real identity beneath the aliases. The chapter ends before the narrative states that name.

Inspector Tyador Borlú addresses the forty-two-member Oversight Committee at Copula Hall, with twenty-one representatives from each city. He identifies the murdered woman as Mahalia Geary, a twenty-four-year-old American archaeologist enrolled in a PhD program at Prince of Wales University in Canada. Her supervisor is Isabelle Nancy, and she worked with the Bol Ye'an archaeological project in Ul Qoma, where she had lived for more than two years. Three years earlier she attended a conference in Besźel and caused controversy with a presentation about Orciny. She later obtained lawful entry to Ul Qoma for her studies, disappeared there about two weeks before the meeting, and was found dead in Pocost Village, which belongs entirely to Besźel.

Borlú has waited several days for a regular committee meeting because his attempts to secure an extraordinary hearing failed. The committee is responsible for assessing possible breaches before surrendering jurisdiction to Breach. National Bloc representative Major Yorj Syedr challenges the case for immediate invocation, arguing that Mahalia might have traveled by an authorized route during the unaccounted period and that the police have not sufficiently interviewed her family or colleagues. He also objects to allowing what he calls an alien power too much authority. Borlú says Corwi has verified Mahalia's circumstances and contacted her parents, who are traveling to Besźel. Committee chair Yavid Nyisemu acknowledges the concern about surrendering sovereignty but says the evidence warrants referral. He ends Borlú's presentation and indicates that the committee will endorse invoking Breach; the actual vote and formal invocation have not yet occurred.

As Borlú considers the committee's powers, he recalls an accident he saw at fourteen: an Ul Qoman van crossed into Besźel space, killing a Besź pedestrian and seriously injuring its driver. Borlú did not see the collision itself, but saw the aftermath and figures of Breach apparently emerge and contain the scene. The memory illustrates the distinction between immediate intervention after an obvious breach and the slower process for referring an unresolved case. Afterward Borlú tells Corwi that he expects a decision within a day or two, though he does not know precisely when the committee will vote.

As they pass Copula Hall, Borlú describes its passport-controlled passageways as the legal way to travel between the overlapping cities. A person may legally leave one city and return to the same physical location in the other after passing through the building's checkpoints. Borlú expects Mahalia's murder inquiry to leave his jurisdiction soon, but the transfer remains prospective as the chapter ends.

Inspector Tyador Borlú and Constable Lizbyet Corwi meet Mahalia Geary's parents at Besźel Airport. The Gearys have been admitted on compassionate visas without the training normally required of foreign visitors, leaving them vulnerable to accidentally acknowledging or entering Ul Qoma. Borlú and Corwi therefore accompany them and arrange close supervision at their hotel while the request to transfer the murder case to Breach remains pending. The parents insist on seeing their daughter before going to the hotel. In the morgue, Hamd Hamzinic uncovers her face and they recognize her in grief; they had asked to view the body, not to perform a formal identification.

At lunch in the Queen Czezille hotel, American embassy official James Thacker joins the group. Plans are being made to arrange lawful passage through Copula Hall so the parents can see Mahalia's archaeological workplace in Ul Qoma. Thacker and Borlú explain that Breach is expected to take over the murder inquiry but operates secretly. Any tribunal would be closed, and the Gearys should not expect to speak to Breach, testify at its proceedings or attend a public trial. No formal handover has occurred yet.

The parents say Mahalia had long been interested in Orciny, which they sometimes conflate with Breach. Mrs. Geary describes Mahalia's relationship with her supervisor, Isabelle Nancy, as argumentative but productive. She says her daughter had recently seemed stressed and had spoken of important progress in her research. Mr. Geary angrily suspects political extremists, naming Qoma First, while Mrs. Geary corrects his recollection of an earlier hostile encounter in Besźel with nationalist opponents there, possibly the True Citizens. The parents' accounts provide leads but do not establish the identity of Mahalia's killer or prove that any organization threatened or murdered her.

After settling the Gearys under police supervision, Borlú wonders aloud whether they should inquire further into Mahalia's conflicts with nationalist and unificationist groups. Corwi questions the point because Breach may soon take jurisdiction. Borlú maintains that the girl deserves Breach's attention but that they remain responsible for the investigation in the meantime.

Despite Commissar Gadlem's instruction to limit further work while the murder inquiry awaits transfer, Borlú reaches Isabelle Nancy at the Bol Ye'an archaeological project in Ul Qoma. Nancy says Mahalia's formal PhD concerned pre-Cleavage artifacts and the interpretation of identity through features such as intricate gear arrangements, not a dissertation on Orciny. Mahalia needed direct access to the objects and also worked at the dig. Nancy recalls her student's earlier enthusiasm for Orciny and David Bowden's theories, but says Mahalia had claimed to have abandoned that interest when enrolling. Nancy cannot verify what she read or investigated privately. She praises Mahalia's intelligence and work ethic while finding the written thesis chapters unexceptional despite the time Mahalia devoted to her research.

Nancy explains that David Bowden's banned 1975 book, Between the City and the City, recast the legend of Orciny as a still-existing secret community hidden between Besźel and Ul Qoma. She calls some of his archival research impressive but regards the theory as untenable; she is not even certain he believed it. According to Nancy, Bowden later repudiated the theory and now teaches part-time at Prince of Wales University while living in Ul Qoma. Borlú confirms some publication details online and reads short excerpts of Bowden's work, but he cannot reach him directly.

That evening Officer Agim Ceczoria calls from the hotel operation: Mr. Geary has escaped supervision and committed breach. Borlú goes to the airport, where Mr. Geary lies unconscious. Ceczoria says an unidentified representative of Breach appeared with Geary at the hotel, declared that he had breached, and ordered his removal. The exact method by which Geary was incapacitated is unknown. Borlú learns that Geary escaped through a ground-floor bathroom window and crossed into a courtyard belonging solely to Ul Qoma while trying to pursue his own leads. Mr. Geary is to be deported. Mrs. Geary was not ordered deported herself, but chooses to leave with him.

Mrs. Geary says Mahalia feared enemies among nationalist movements and that her husband had taken addresses and a phrase book to investigate them. These are her allegations, not established explanations for the murder. At the aircraft, with Mr. Geary still unconscious, Borlú helps stow Mrs. Geary's bag and covertly removes a slip of paper from its side pocket. Back inside the airport he reads the copied name and address of True Citizens, providing a new investigative lead without establishing their involvement.

Borlú and Corwi go to the headquarters of the nationalist True Citizens, using the address Borlú covertly took from Mrs. Geary. Although the Oversight Committee has not yet invoked Breach, Corwi questions why they should continue investigating when jurisdiction will likely pass soon. The building is in a total Besźel street near crosshatched territory. Several intimidating members block the entrance and refuse to admit the officers without search authority. Borlú pretends to report an arranged backup check-in over his radio, although no such arrangement has been made. When he mentions the alias Byela Mar, the men appear uncertain; when he names Mahalia Geary, they recognize her and suggest that her criticism of Besźel has brought trouble on herself.

A well-dressed barrister, Harkad Gosz, arrives by car and identifies himself as counsel for True Citizens. He already knows Borlú's name and the purpose of the visit. Gosz characterizes Mahalia's former interest in Orciny and her subsequent archaeological studies in Ul Qoma as evidence of suspect motives or hostility to Besźel. Borlú asks whether Gosz is suggesting she was an Ul Qoman agent; Gosz does not establish that allegation. When Borlú asks how the men know Mahalia's identity and Gosz knows details of her research, the lawyer notes that conference papers, university research, and public information can be found online, and a member says he picks things up. Borlú has not seen Mahalia's name in the press, but recognizes that information might have leaked or been published without his knowing. Gosz warns that continued uninvited questioning could bring a harassment complaint and tells Borlú to pass his regards to Commissar Gadlem.

After leaving, Corwi speculates that True Citizens act as street-level allies of the National Bloc and that Major Syedr might have arranged the lawyer's intervention or supplied information. Neither officer has verified that chain of contacts, and they have no evidence that the group murdered Mahalia. Borlú reiterates that he wants the case referred to Breach but believes the remaining time should be used to gather information. On the way back they buy American-style coffee, which Corwi dislikes.

Early the next morning Commissar Gadlem summons Borlú and produces the Oversight Committee's official refusal to invoke Breach in Mahalia Geary's murder investigation. Its letter says that newly discovered evidence does not establish a violation of the boundary between Besźel and Ul Qoma. Gadlem shows him grainy surveillance footage from a private bank camera outside Copula Hall, apparently depicting Mikyael Khurusch's dirty white van entering the official crossing from Besźel toward Ul Qoma on the night before Mahalia was found and returning a little over an hour later. Borlú recognizes its license plate. The committee reports that the vehicle passed through official checkpoints with apparently acceptable documents, bringing the body between cities by an authorized route rather than by breach.

Borlú objects to the sudden emergence of the footage and the reversal of the expected decision. He and Gadlem find the circumstances suspicious but agree that, if the vehicle crossed at Copula Hall, the committee's jurisdictional conclusion is correct. Even smuggling a prohibited object through a checkpoint is not breach, although crimes involving the object, papers, or border entry may still be prosecuted. A direct unauthorized crossing between the overlapping cities would be breach regardless of what was transported. The officials have no useful contemporaneous border-guard records beyond the apparent passage, so the documents' authenticity is not independently resolved. The case is therefore to proceed through ordinary law enforcement.

Gadlem directs Borlú to travel to Ul Qoma as an invited consultant to the local militsya's Murder Team, because the investigators now believe Mahalia was killed on Ul Qoman territory while offenses involving the van and disposal of her body occurred in Besźel. Borlú asks to take Corwi, but Gadlem refuses and emphasizes that Borlú will assist, not command, the Ul Qoman team. Gadlem also discloses that Major Syedr phoned angrily that morning after hearing of the previous day's True Citizens visit, objecting to Borlú linking his name to the organization. The surveillance footage surfaced only hours later. This timing raises suspicions of political interference, but neither man knows who found the footage or why. Taskin Cerush can relay only unverified rumors about committee members' reactions.

With his overseas orientation scheduled in two days, Borlú prepares for the assignment. A used, banned copy of David Bowden's Between the City and the City, which he had ordered online, arrives by expedited post. He speaks with Sariska and Biszaya, then tells Corwi that she cannot accompany him. They discuss how unexpectedly the old footage was located. Borlú proposes making additional inquiries into the van's border crossing before departure, calling their work unauthorized because Corwi is supposedly off the case, although he privately acknowledges that he can authorize her efforts and would bear any resulting disciplinary risk himself. She agrees.

Borlú and Corwi return to Mikyael Khurusch and question him about the Any Qualified Driver (AQD) pass that would have allowed his van to cross repeatedly between Besźel and Ul Qoma through Copula Hall. Borlú infers from the surveillance footage that the driver must have presented apparently acceptable papers. Khurusch eventually admits that he left his permit in the van when it was stolen and concealed that fact because he feared losing his border-crossing privileges. His record shows an earlier official warning for leaving travel papers in a car; he also acknowledges paying a border official to have that earlier violation treated as a warning. He denies lending the van or being paid to facilitate the murder. Borlú accepts that Khurusch's alibi excludes him as the apparent killer but takes him into custody for improper pass storage and failure to report the theft.

Borlú asks Corwi to compile records of vans stolen on the relevant night, including their travel permissions and owners' previous violations. She finds thirteen recorded thefts, three involving vans subsequently burned or vandalized. Three of the stolen vans had Ul Qoma passes, and all three owners had previous warnings for improperly storing those documents. The other two pass-holding vans belonged to Gorje Feder and Salya Ann Mahmud and were found abandoned the following morning. The investigators have not verified whether the passes were still in those vehicles, nor do they establish a definitive order of theft. Corwi also cannot obtain a baseline rate for AQD permits among Besźel vans, so the pattern's statistical significance remains undetermined.

Borlú proposes that thieves seeking border-crossing documents may have consulted records of previous storage violations, tried the vans in succession, and obtained a usable permit from Khurusch's. This is a reconstruction, not proven theft chronology or proof of access to confidential files. The possibility that someone had access to official records unsettles both officers. Borlú acknowledges that their correlations are insufficient to establish a criminal conspiracy, and they no longer know whom they can safely inform. With Borlú due to travel to Ul Qoma and Corwi being taken off the case, they agree to remain in contact and keep investigating discreetly.

The narrative enters Part Two, Ul Qoma. Constable Dyegesztan drives Borlú through Copula Hall in a Besźel police car but is not crossing to stay: his orders are to return after delivering Borlú to the checkpoint. The officer's papers are carefully inspected. Between the Besźel and Ul Qoman gates lies a short stateless stretch of roadway, one of the few places where travelers can openly view both cities. Senior Detective Qussim Dhatt of the Ul Qoman militsya meets Borlú at the far side and takes him into his car.

As Dhatt drives through Ul Qoma, Borlú recalls the accelerated two-day orientation he completed before crossing. Embassy tutors taught him local language, civic rules, and how to reverse the habits of seeing and unseeing that have governed his life in Besźel. A computerized simulator progressively emphasized Ul Qoman buildings and minimized familiar Besźel landmarks. Borlú now sees places he formerly had to ignore and deliberately unsees the Besźel streets he knows. The modern financial buildings, traditional structures, and preservation measures adopted after UNESCO criticism also illustrate the two cities' economic and architectural differences.

Dhatt makes clear that Mahalia Geary's murder is now an Ul Qoman investigation. Borlú is a consultant, has no Ul Qoman police powers, and must treat independent excursions as tourism under his temporary permit. Dhatt has limited results from local interviews and still does not know where the murder occurred within Ul Qoma or where Khurusch's van went after leaving Copula Hall. Borlú wants to visit the Bol Ye'an excavation and speak to Mahalia's adviser and classmates.

As they arrive at Borlú's hotel, Dhatt reports another concern. Ul Qoman officers interviewed Yolanda Rodriguez, Mahalia's best friend and a fellow student, shortly after Mahalia's death. Yolanda was distraught, said she had someone to look after her, and left. The previous day an anonymous student called police to say that Yolanda had not been seen for some time and was not answering her phone. Dhatt cautions that she might merely be ill or unavailable; Borlú says that not knowing where she is constitutes a disappearance regardless of its cause. Dhatt eventually agrees to use the term. No harm to Yolanda has yet been established.

From his Ul Qoma hotel, Borlú updates Corwi on the investigation. Mahalia Geary's student room yielded little beyond books with dense annotations, ordinary correspondence, and a computer that revealed no relevant information; the investigators have made copies of her annotated texts. Yolanda Rodriguez's nearby room contains more personal possessions, but her computer is gone. Colonel Muasi has required Borlú to surrender his gun because he has no Ul Qoman firearms authorization. Borlú and Corwi use a prearranged code phrase on their call because they fear, without proof, that their conversations may be monitored.

Dhatt postpones the planned visit to Bol Ye'an until morning, so Borlú goes out alone that night. He walks across Ul Qoma, consciously ignoring familiar parts of Besźel, and views the excavation from an elevated street beyond its perimeter without entering the dig. Two local officers challenge him, check his documents and insist on escorting him back to the hotel. Dhatt expresses displeasure the next morning but takes Borlú to the site as planned.

At Bol Ye'an, project head Bernard Rochambeaux says he barely knew Mahalia and has little information about Yolanda. Dhatt tells Borlú that Rochambeaux has a verified alibi for the time of Mahalia's death. David Bowden appears at the site and says he has come looking for his sole supervisee, Yolanda Rodriguez, who missed a meeting. He reacts with alarm when the investigators tell him she cannot be located. Isabelle Nancy questions Rochambeaux's professed unfamiliarity with Mahalia, recalling that he was present at the Besźel conference where her questions about Orciny, Breach and disputed areas caused controversy. Nancy confirms that Mahalia and Yolanda were best friends, says Yolanda was rumored to be seeing a local man, and remains uncertain whether anything serious has happened to her.

Borlú and Dhatt interview the other academics and archaeology students. Rebecca Smith-Davis reports that Yolanda had become more interested in Orciny than Mahalia appeared to be recently, although these judgments are based on the students' impressions. Robert, another student, reveals that he made the anonymous call reporting Yolanda's absence. During the interviews Dhatt begins treating Yolanda as an official missing person. None of the students raises Breach as a possible explanation, an omission the investigators notice but cannot explain. As they leave, security guard Aikam Tsueh anxiously asks whether Mahalia's killer could have escaped Ul Qoma. He provides his contact number; Dhatt says most guards had alibis and agrees to check Tsueh's. His conduct raises questions but establishes no involvement in the crime.

In an Ul Qoman teahouse, Borlú and Senior Detective Qussim Dhatt discuss how to coordinate questioning after Borlú's intervention in the earlier interviews. Dhatt is more cooperative than before, though tension remains. Their discussion touches on Ul Qoma's immigrant population, strict admission tests and detention camps. Dhatt confirms that Aikam Tsueh has an alibi: he was out with several students on the night Mahalia died. The detectives review the movement of the van and possible cooperation between people in the two cities. Dhatt speculates that someone involved in the legal crossing used a contact in Copula Hall or the traffic bureaucracy to bring relevant surveillance footage to investigators' attention, thereby avoiding Breach jurisdiction. This is a theory, not evidence identifying such a contact.

When Dhatt asks how Borlú originally identified Mahalia, Borlú reluctantly reveals that he received an anonymous call from Ul Qoma from someone who said he recognized the victim on a Besźel police poster. Borlú believes that using this information may implicate him in breach, but Dhatt is more concerned with tracing the caller. Borlú says he inferred that the man was a unificationist from his language and views, although the caller never stated any affiliation. Dhatt takes the disclosure as a promising lead and drives to an Ul Qoman unificationist meeting place.

Unificationist organizations are not legal in Ul Qoma, although the government has become more tolerant of some dissenting gatherings under President Ul Mak and his predecessor. Dhatt pushes into the building and gathers five occupants, then orders them to repeat a phrase so Borlú can identify the voice from the telephone. He assaults a male occupant who hesitates and hits him again during the coercive questioning. One of the younger men, Dahar Jaris, sounds familiar to Borlú, but he cannot confidently identify him from the forced repetition of a different phrase. Borlú stops Dhatt from continuing and says none of the five made the call. The source leaves open whether this reflects uncertainty, reluctance or both.

On the return trip Dhatt suspects that Borlú is refusing to pursue the lead because he fears punishment for acting on information obtained through breach. He suggests that a minor violation could be overlooked to resolve a more serious crime, but Borlú denies that this is his reason and insists that breach is taken seriously in Besźel. Dhatt drops him at the hotel, proposing further interviews with Nancy and Bowden. Borlú then calls Corwi and asks her to find background information on Dhatt. She warns that obtaining confidential militsya personnel files would be impractical and provocative, but agrees to see what she can discover.

Borlú and Dhatt have no new sightings of Khurusch's van after its passage through Copula Hall. They travel by Ul Qoma's renovated Metro to visit David Bowden, who lives in a cramped second-floor apartment crowded with books, maps and artifacts associated with both cities and the Precursor Age. Bowden recounts how the Ul Qoman authorities once housed foreign residents together, making them easier to observe. He says he has no firm alibi for the time of Mahalia's murder, though a neighbor might have heard him at home. In his study Borlú notices papers in an unfamiliar script that Bowden identifies as unsolicited crank mail, purportedly written in the language of Orciny. Bowden dismisses its significance.

Bowden explains that the antiquities concentrated in Ul Qoman soil and the strict rules on their export draw archaeologists to the city. He says his academic status remains precarious because of Between the City and the City, the book in which he once advanced the reality of Orciny. He states that he disavowed the theory, while maintaining that much of its underlying research is sound. At the conference in Besźel years earlier, Mahalia approached him as an admirer and asked to work with him. Bowden says she had smuggled his banned book into Besźel and told him that she intended to leave it in the university library's history section for others to find. He warned her to dispose of it or he would report her, rejected her approach and thereafter avoided contact with her. The text does not establish that the book was ever actually placed in the library.

Bowden is more concerned about Yolanda Rodriguez, his only supervised doctoral student, whose disappearance remains unexplained. He says she had recently asked him about Orciny and dissensi, disputed places claimed by both cities, even though she knew his rejection of the theory. He describes some disputes as openly known and others as supposed secret disputes, and offers Dhatt a list while noting that his information may be outdated. He wonders whether Mahalia influenced Yolanda, but does not know. Borlú asks if anyone might have a grievance against Bowden; Dhatt mentions a break-in at his apartment a few weeks earlier from which nothing was stolen. Both investigators suggest that someone interested in Orciny-related research could have been targeted, but they have no evidence tying the break-in, the women's cases or the theory to a common perpetrator. Bowden is visibly alarmed.

After their visit to David Bowden, Dhatt sends officers to examine locations on the list of disputed areas and asks a subordinate to expand it. In his hotel room Borlú reviews Mahalia Geary's draft dissertation chapters and photocopied marginal notes. Two chapters are substantially finished and two are sketchier; their restrained, unremarkable prose contrasts with the intense, questioning annotations in her textbooks. Bowden's banned book strikes Borlú as containing ingenious observations about pre-Cleavage artifacts, combined with unsupported conclusions about a hidden city.

Late that night Dahar Jaris, the young Ul Qoman unificationist whose voice had sounded familiar during Dhatt's coercive questioning, telephones Borlú. Jaris confirms that he made the earlier anonymous call identifying the murdered woman to Besźel police and thanks Borlú for not pointing him out. He says Mahalia, whom he knew as Marya, used unificationist libraries and contacts to investigate Orciny, not to advance unificationism. According to Jaris, she told him she had found Orciny and was helping people associated with it. He describes locations which residents of both cities each assume belong to the other, distinguishing these purported places from ordinary disputed zones. These are Mahalia's reported claims, not independently established facts.

Jaris says that shortly before her death Mahalia had become frightened and angry, wondered aloud whether her actions amounted to restitution or crime, warned that people who knew about Orciny might be in danger, and began carrying a knife. Jaris believes she was deceived by Orciny and killed after discovering something, but he admits that he does not know what she was doing or what happened to her. Fearing for his own safety, he says he is leaving and will discard the phone. The conversation does not confirm that Orciny exists or that anyone associated with it killed Mahalia.

Troubled by the call, Borlú telephones Mrs. Geary in the United States. She confirms that Yolanda Rodriguez was Mahalia's trusted friend and becomes upset at the possibility that Yolanda is missing; Borlú stresses that no harm has been established. Mrs. Geary recalls an unnamed man Mahalia knew through politics who appeared interested in her romantically, but says Mahalia did not return his interest because the situation was too complicated. She also explains that her husband intended to question hostile groups across the political spectrum, beginning in Besźel because addresses there were easier for him to obtain. After the call, Borlú returns to sleep. The chapter ends the following morning when Dhatt calls from downstairs and announces that someone has sent a bomb, without yet identifying its recipient or sender.

At the Bol Ye'an archaeological site, the Ul Qoma bomb squad examines a parcel that security guard Aikam Tsueh flagged because it felt unusually heavy and hard. Although checking the mail is not normally his responsibility, he says he noticed that the outer envelope bore only the site's address. Inside a second envelope, marked with David Bowden's name, a pull strip labeled in Besź would trigger a directed explosive charge. Bomb technician Tairo confirms that the device was intended to seriously injure or kill the person opening it, rather than merely frighten them. The parcel was posted in Besźel, and its outer envelope bears an Illitan phrase, The heart of a wolf, from an old patriotic song. No fingerprints or other evidence identify the sender.

Dhatt and Borlú question Tsueh about how he noticed the parcel and why he handled the mail. He explains his suspicion but cannot add information about its sender. The investigators consider whether someone targeting Bowden might have used a package from Besźel and the two-envelope arrangement to evade his caution, but this remains speculation. Professor Nancy recalls that Bowden received hostility and threats years earlier over his banned Orciny book; she cannot identify a past assailant or connect those incidents to this bomb. Borlú proposes Ul Qoman nationalist involvement, possibly under the name Qoma First. Dhatt replies that Qoma First is essentially a press label, not a known organization with a location or membership list, though he does not deny the presence of secretive ultranationalists.

Kai Buidze, the site's chief security guard, says Tsueh is friendly with some students, including Yolanda Rodriguez, but not especially close to Mahalia. When Borlú asks why none of the foreign students mentioned Breach, Buidze says they may fear drawing attention to their own minor boundary violations. He describes young visitors looking into the neighboring city or possibly taking small souvenirs from crosshatched areas, emphasizing how difficult such acts are to prove and how staff tolerate behavior that does not become blatant. His explanation does not establish specific breaches by named students or a connection to the murder.

While the investigators finish questioning site staff, Dhatt receives a call from officers sent to Bowden's apartment. They find no answer and Bowden is not there, even though he knew about the bomb and the planned visit. His absence is alarming, but the chapter does not establish where he has gone or formally determine that he is missing.

After officers fail to locate David Bowden, Dhatt wants to question the young unificationist Dahar Jaris again. Borlú says Jaris has fled, prompting Dhatt to demand how he knows. Borlú admits Jaris called him the previous night and confirmed making the original anonymous call to Besźel. Dhatt is angry that this was withheld and suspects Jaris may be involved in Mahalia's murder or the attack on Bowden. Borlú disputes that conclusion, describing Jaris as frightened and doubting that his involvement would explain the first helpful tip or the border-crossing operation. The two officers also confront each other about information they have not shared, including Bowden's earlier break-in. Borlú suspects the academic UlHuan is a government informant, but that suspicion is not established.

At a bar frequented by Ul Qoman police, the two agree to work more openly together. Borlú apologizes for the delay in reporting Jaris's call and describes Jaris's account of Mahalia's alleged discovery of Orciny. Dhatt rejects Orciny as a real secret city but acknowledges that people could act violently because they believe in it. Their cooperation improves without resolving the case or the doubts surrounding Jaris. Later, Dhatt invites Borlú to supper with his wife, Yallya. The couple live near the same crosshatched park Borlú sees from his own home in Besźel. Borlú enjoys their hospitality but remains preoccupied with the unresolved disappearances and the possibility of being observed.

After dinner Borlú walks alone through Ul Qoma and passes near his own apartment in the overlapping Besźel streets. He notices an elderly woman whose clothing and position he cannot confidently assign to either city. Other indistinct figures appear nearby. When she seems to move toward him he retreats, and the figures withdraw into darkness. Borlú cannot establish whether any of them was in Ul Qoma, in Besźel or violating the separation. The unsettling encounter provides no independent evidence of Orciny. He then returns to an overlook above Bol Ye'an and observes the site for an hour before returning to his hotel.

At the hotel, Borlú has a short message printed on plain paper: Urgent. Come ASAP. Don't call. The next morning he dresses in locally acquired Ul Qoman clothing, with his required visitor's badge still present but inconspicuous, and watches the dig from a distance. He pays a young street courier to deliver the sealed message specifically to Aikam Tsueh. Tsueh promptly leaves the site, apparently believing the message is from someone he is expecting. Borlú follows him by street and bus to an apartment in a poor outer Ul Qoman housing complex. On hearing Tsueh speak with someone behind a partly opened door, Borlú rushes forward and shoves him through the entrance. Inside he finds Yolanda Rodriguez, who screams and backs away. Borlú blocks the exit and says he wants to help her, asserting that others may want to hurt her. The chapter ends with Yolanda crying, without establishing whether her reaction is fear or relief or who, if anyone, is pursuing her.

Inside the apartment where Yolanda Rodriguez is hiding, Aikam Tsueh tries to attack Borlú. Borlú trips him, pins him to the floor and leaves him with a bleeding nose. He falsely tells Yolanda that he has a gun, although the Ul Qoman authorities took his weapon when he arrived. Yolanda eventually calms Aikam and allows Borlú to speak with them. The sparsely furnished, abandoned flat contains boxes of books and belongings, a laptop and a printer, and a photograph of Yolanda with Mahalia Geary. Aikam has been bringing supplies and asking about the murder and ways to leave Ul Qoma because Yolanda is terrified and wants to escape without attracting attention. Borlú silences a call from Dhatt and promises not to contact the militsya.

Yolanda says she fled after Mahalia's murder because she believes Orciny's agents killed her friend and are looking for her. Her account is based largely on what Mahalia told her, not on firsthand evidence of Orciny. She says Mahalia maintained a conventional archaeology PhD as cover for her real interest in the purported third city. According to Yolanda, Mahalia received letters in an old, pre-Cleavage script after her controversial Besźel conference appearance. Yolanda reports seeing some letters and says Mahalia described correspondence and assignments involving addresses in disputed areas, delivery of messages, and information about the artifacts being excavated. She claims Orciny considered the objects its own pre-Cleavage property and may have used Mahalia to track discoveries. Borlú does not establish who wrote the letters, whether the supposed Orciny contacts exist or whether the artifacts were deliberately stored.

Yolanda also says Mahalia deliberately avoided breaching for fear of attracting Breach's attention, and that in her final weeks she withdrew from the dig, studied intensely and expressed fear that her activities might be implicated in theft or some other wrongdoing. Yolanda believes Bowden concealed continuing knowledge of Orciny, although he publicly repudiated his early theories. These are Yolanda's interpretations, and she cannot identify the alleged pursuers or confirm the fate of Bowden. Borlú offers to help her leave the city, then raises the possibility of deliberately breaching into Besźel to attract Breach's protection. Yolanda rejects the idea because Mahalia portrayed Orciny and Breach as enemies in an ancient conflict, while Yolanda herself wonders whether they might instead collaborate or even be the same organization. The chapter ends with her speculative assertion, not a revelation establishing any connection.

Yolanda initially tries to prevent Borlú from leaving her hiding place, fearing that anyone who sees him will discover her location. Borlú says he cannot protect her effectively in Ul Qoma and promises to arrange her removal to Besźel, where he can use his police contacts, before helping her get farther away. She remains distrustful and protests that both cities may be compromised. He instructs Aikam to stay with her and stop attracting attention at Bol Ye'an, noting that the abandoned flat has enough food and basic supplies for another day or two. Borlú escapes through a vacant, fire-damaged apartment on the ground floor and returns to public streets before switching his phone back on.

Borlú telephones Dhatt from a public booth and arranges to meet near Kaing Shé Station, insisting that Dhatt come alone. He watches Dhatt from a distance before approaching. Dhatt is furious that Borlú operated independently and refuses to reveal Yolanda's location, but listens as Borlú explains her fears and proposes relocating her secretly. Borlú does not claim that Orciny is real or that the authorities are definitely compromised. He argues that Yolanda will not cooperate with an official intervention and that he has the contacts needed to conceal her in Besźel and eventually move her beyond the two cities. Dhatt says another search of Bowden's apartment found no signs of forced entry or struggle, but did find a one-word note in an unfamiliar script. Isabelle Nancy believes it may be an archaic Precursor warning, though she is not fully certain of its reading. Neither the note's sender nor its relevance to Bowden's whereabouts is established.

After further disagreement, Dhatt agrees to help with an unofficial departure. The detectives avoid their usual lodgings, walk through crowds and crosshatched streets, and consider using Borlú's existing exit permission and an invented official identity to secure passage for Yolanda. No border crossing or extraction has yet occurred. Dhatt leads Borlú to a basement club and provides a telephone, from which Borlú calls Corwi in Besźel. He asks her to discreetly meet him and Dhatt with a car and weapons, book a hotel outside normal police arrangements, and help get Yolanda onward. To conceal Yolanda's identity from ordinary arrangements, he describes the accompanying woman as another undercover officer.

Corwi reports that an unidentified caller with a North American-sounding voice has repeatedly contacted her desk, asking about arrests, the missing girl and Borlú's return. Borlú infers that the caller is David Bowden, who might be avoiding traceable Ul Qoman police lines, but Corwi has not confirmed the man's identity. Borlú asks her to tell the caller to use Yallya's mobile phone, borrowing a number from Dhatt as a less obvious channel of communication. The chapter ends with the connection to Corwi severed before any confirmed contact with Bowden or the intended border transfer.

Borlú goes with Dhatt to the Ul Qoman militsya office while they prepare to bring Yolanda Rodriguez to Besźel without disclosing her identity. Dhatt has borrowed his wife Yallya's phone over her objections, hoping that the unidentified caller who contacted Corwi will use it. After several calls intended for Yallya, David Bowden reaches Borlú on the phone and confirms that he is hiding and afraid. He refuses to disclose his location or let Borlú collect him, but wants to leave Ul Qoma. Dhatt considers obtaining additional papers and police clothing for a second person. Corwi later confirms that she has arranged the Besźel-side documents and will meet the party at Copula Hall at eight the following evening. Borlú subsequently tells Bowden that, if he wants to go, he must be outside the main traffic gate at seven p.m. Bowden does not confirm that he will come.

While completing administrative work and concealing his plans, Borlú spends much of his last day in Ul Qoma moving between taxis and sightseeing routes to make any surveillance difficult. A Kurdish driver tells him about his year in a refugee camp and three years preparing for citizenship, including training to unsee Besźel. Borlú notices a man watching them at a canal but cannot establish that he is being followed. He finally reaches Yolanda's hideout and tells her to take her papers and follow the officers' instructions. Aikam Tsueh protests at being left behind, but Yolanda promises to contact him from Besźel and Canada and goes with Borlú to meet Dhatt.

Dhatt brings an unmarked police car, an Ul Qoman militsya uniform for Yolanda and a police jacket for Borlú. With Yolanda disguised as an officer, they drive to the Ul Qoman side of Copula Hall, pass the outer guards and enter the passage between the official checkpoints. Borlú sees what he believes is Corwi in police uniform on the Besźel side. A cloaked man pushing through the crowds approaches them. Dhatt urges Yolanda forward while Borlú confronts the stranger, who removes his scarf and identifies himself as Bowden. Bowden produces a pistol but holds it awkwardly rather than aiming it at Borlú.

Gunfire suddenly breaks out. Borlú hears Dhatt shouting and sees him wounded in the shoulder and crouching over Yolanda, who is down with blood on her face. Dhatt reports that she has been shot. Borlú looks down the hall toward Besźel and sees crowds fleeing a man raising a rifle from the opposite side of the checkpoint. The chapter ends with the rifleman preparing to aim. His identity, the motive for the shooting and Yolanda's final condition are not yet established within this chapter.

The shooting at Copula Hall continues. Borlú tackles David Bowden to the ground as a rifle bullet strikes the wall behind him, and takes the pistol Bowden is holding. Dhatt says he has been wounded and that Yolanda was shot in the head. Borlú sees Yolanda dead, guarded by Dhatt, while police and travelers panic on both sides of the passage. The rifleman, who fired from the Besźel side, moves into the crowd to escape. Although the shooting crosses the cities' boundaries, it occurs through the legal physical corridor of Copula Hall, and Borlú understands that this does not constitute breach: ordinary police still have jurisdiction.

Unable to get directly through the border checks, Borlú leaves Bowden with Dhatt and drives Dhatt's police car around the outside of Copula Hall while remaining in Ul Qoma. He reaches a location physically near the Besźel entrance, climbs onto the vehicle and looks across the overlapping streets. He spots a man he believes is the rifleman among people fleeing into Besźel. Borlú has seen him before but cannot place him. Neither the source nor Borlú identifies the shooter by name in this chapter.

Borlú pursues on foot through Ul Qoma while the rifleman remains in Besźel. Borlú keeps his direct attention on Ul Qoman streets and follows the man in the edge of his vision, respecting the separation even as they pass through physically adjacent, crosshatched routes. The killer approaches a street belonging solely to Besźel, where Borlú will no longer be able to follow. He briefly looks at Borlú and gives a triumphant smile. Borlú raises Bowden's pistol and deliberately shoots across the cities' boundary, striking the man in the chest and killing him.

Bystanders cry out that a breach has occurred, and figures who identify themselves as Breach appear immediately. Borlú is seized and carried through spaces whose relationship to either city he cannot comprehend. Something touches him, and he loses consciousness while hearing the repeated declaration of Breach. The chapter ends without a confirmed public identification of the killer or an explanation of what Breach intends to do with Borlú.

After being seized by Breach for shooting across the border from Ul Qoma into Besźel, Borlú awakens in a locked, undecorated room, unsure where he is or how long he has been unconscious. Three impassive figures question him. The older man identifies the rifleman Borlú killed as Yorjavic, a former Besźel Armed Forces soldier who served as a sniper for six years. Borlú recognizes the name and remembers seeing him among the True Citizens during his earlier confrontation with the nationalist group. Breach reports that Senior Detective Dhatt is recovering but will never fully regain movement in his right arm, while Yolanda Rodriguez is dead. The interrogator explains that Yorjavic's shots through the designated corridor of Copula Hall did not breach the cities' boundary. Borlú's deliberate shot across the divided streets did, and therefore he is in Breach's custody.

During further questioning the older interrogator says Yorjavic was drawn into breach when Borlú shot him, which brings Breach authority over that incident. The interrogator says Yorjavic had instructions from somewhere other than True Citizens, without identifying who issued them. Breach can decide what sanctions apply to Borlú, and the questioning forms part of that decision. The agents demand an account of Mahalia Geary, Yolanda and the recurring references to Orciny. Borlú recounts the investigation. When he attempts to rush past his guards, they easily restrain him. He interprets the repeated questions as evidence that Breach itself is trying to investigate the Orciny story and might fear an unknown organization operating outside its control. The interrogator repeatedly insists that no place called Orciny exists; Borlú's interpretation is not a finding that a third city is real.

The agents show Borlú recordings of interviews with David Bowden, Aikam Tsueh and Dhatt. Bowden tells Ul Qoman interrogators that he hid because someone was pursuing him and obtained a gun for protection, but again denies Orciny's existence. Aikam weeps throughout the questioning shown. Dhatt, his arm in a sling, rejects belief in Orciny while insisting that unexplained access to information and the shootings require investigation. Their statements do not establish the reality of Orciny or identify the people who orchestrated the attacks.

Borlú infers that Breach is concerned by the recurrence of the Orciny story and offers to help pursue whoever killed Mahalia and Yolanda, bargaining for a more favorable outcome to his own case. The agents do not release or accept him as an equal partner, although they suggest his treatment may improve if he cooperates. Borlú ends by explaining that Mahalia's distinctive habit of annotating books suggests where evidence of her findings may have been left. He says he knows where to look, but the chapter ends before he retrieves anything.

After spending much of the night watching police interrogation recordings from both cities, Borlú is shown questioning of Corwi, who admits helping with an attempted border transfer but denies further knowledge despite threats to her employment. Breach also shows him interviews with Biszaya and Sariska and with Besźel ultranationalists acquainted with Yorjavic. Several nationalists deny knowing why he acted, although one describes a culture of following instructions without asking questions. The Breach interrogator says this leaves open the possibility that Yorjavic was connected to something more concealed than True Citizens. However, the search of Yorjavic's apartment, his financial records, and Breach's own prior observation reveal no confirmed Orciny connection or unusual affiliation.

The older Breach interrogator then escorts Borlú out of the detention building. Borlú cannot tell which city it occupies and initially assumes that they must have emerged into Ul Qoma because of their destination. The man tells him to call him Ashil and addresses Borlú as Tye, a name that can plausibly belong to either city. Ashil warns him that he remains in Breach and is being watched. As they walk through crosshatched streets, Ashil leads him across the boundary without going through Copula Hall. They buy breakfast at a Besźel stall using Besźmarques, then orange juice in an Ul Qoman shop using dinars. Ashil guides Borlú to perceive the sights and sounds of both cities at once, explaining that being in Breach means being in both rather than neither. Borlú is still a breacher under supervision, not an inducted agent.

Traveling by Ul Qoman Metro, Besźel tram and on foot, Ashil takes Borlú to the Ul Qoman university library. He shows a Breach identification to pass the guard. In the history section, Borlú searches for an unclassified copy of David Bowden's banned book, Between the City and the City. He finds a worn copy lacking an ordinary library classification mark, with numerous small annotations in red, black and blue ink. Borlú recognizes the dense marginal notes as Mahalia's style and identifies the book as where she recorded her investigation, including skeptical reactions and references to other historical scholarship. The notes themselves have not yet been comprehensively examined or independently verified. As Ashil inspects the volume, Borlú believes it may contain the information that brought Mahalia into danger.

Still in Breach custody, Borlú is given bound colour copies of Mahalia Geary's annotated copy of David Bowden's Between the City and the City. He studies successive layers of her handwritten arguments while observing Breach agents moving through spaces that overlap Besźel and Ul Qoma. Borlú suggests that their own existence makes another hidden community conceivable, but Ashil and the other agents do not accept this as evidence of Orciny. In a tense meeting, Breach members debate and vote before Ashil takes Borlú to the Bol Ye'an excavation. Ashil says their purpose is to investigate the circumstances of Borlú's breach and forbids questioning the academics and students.

At the excavation, security officer Buidze explains that artifacts are stored in locked cabinets after the day's work and everyone leaving the site is searched. Borlú checks older, cloth-wrapped finds and uncovers a modern piece of painted door wood where a brass mechanical artifact should be. The catalogue identifies three other old finds that have likewise been replaced with ordinary objects. Borlú infers that Mahalia sometimes volunteered to lock up when she was not scheduled, removed older artifacts less likely to be noticed, concealed them in her clothing, and dropped them in the crosshatched fringe of a park adjoining the excavation. He demonstrates how someone moving through Besźel could later retrieve the items. The missing artifacts establish substitutions, but the handoff, recipient, and purpose remain Borlú's reconstruction rather than observed facts. He argues that such a transfer would constitute breach.

Back at the Breach quarters, agents discuss mounting small breaches and fear an impending confrontation without knowing its source. Borlú remains confined. He changes how he reads Mahalia's marginalia, examining later objections alongside her earlier enthusiastic annotations. Her late references to Sherman, Rosen, and Vijnic lead him to writings that reject Bowden's Orciny theory. He concludes that Mahalia had abandoned her belief in Orciny and proposes that this change, rather than her discovery of a real third city, was why she was murdered. The final assertion is Borlú's new investigative deduction, not yet independent proof of the killer's motive.

Borlú remains confined by Breach, and Ashil again refuses to let him contact Corwi or Dhatt. He asks the agents to compare Mahalia's original excavation lock-up roster with the sheets signed when the keys were returned. The important nights, he argues, are those when she unexpectedly volunteered to replace whoever was scheduled, possibly after receiving instructions. There are only a few such dates, and not every changed shift need have involved a theft. Police surveillance places Yorjavic away from the park on at least two of those nights; Syedr is accounted for at Chamber of Commerce trade events on four.

That connection prompts Borlú to request guest lists for the receptions accompanying the trade events. Five companies attended on all the relevant dates. One is CorIntech, whose delegation was headed by Gorse from its parent company, Sear and Core. Ashil confirms that Gorse, identified as the parent company's CEO, attended every such event. Borlú proposes that corporate representatives rather than nationalist leaders arranged the retrieval of Precursor artifacts. His theory is that Sear and Core wanted to test their rumoured properties and induced Mahalia to supply them by making her believe she was dealing with Orciny. The attendance records establish a striking correlation, not yet that the company directed the theft or murder. Ashil questions the proposed motive but agrees to investigate. He begins trying to assemble a conspicuous Breach force, explaining that foreign company officials may not respond to Breach as local citizens do and that intervention could damage a major Besźel business.

Before the agents can gather, Ashil receives news that two buses carrying refugees have been ambushed and crashed into the crosshatched Finn Square area, hitting a wall in Ul Qoma. The passengers, unfamiliar with the cities' enforced separation, spill into both cities. Ashil reports coordinated unificationist actions and widespread breaches, and Breach orders an extraordinary complete lockdown of both cities, including public streets and ordinary international travel. Borlú argues that the apparent uprising is a diversion arranged by whoever is behind the artifact operation, perhaps triggered when Breach inquiries into Chamber of Commerce records were noticed. He is concerned that private aircraft may evade the restrictions affecting national carriers and insists they must reach the Sear and Core building. The chapter ends with that unproven but urgent accusation, before the company is confronted.

Borlú and Ashil travel through the unrest unleashed by unificationists during the extraordinary Breach lockdown. They see young people breaking the separation rules, a mixed-city unificationist group painting joint slogans, and Breach agents using severe force to stop demonstrators. Ashil says Breach has lost some avatars. Its decentralized decision-making leaves the two of them to pursue Borlú's corporate theory without reinforcements: Ashil believes the possibility warrants investigation but has not convinced the other agents. A helicopter appears over the riverside Sear and Core headquarters, and they realize it is arriving to collect passengers rather than leaving.

At the corporate building, Besźel security guards recognize Ashil's authority and let them reach the roof. Near the waiting helicopter are two armed True Citizens, a man introduced as CorIntech regional head Ian Croft, and Besźel opposition politician and Chamber of Commerce member Mikhel Buric. Borlú identifies Buric as the likely political intermediary who could have exploited Mahalia's belief in Orciny to collect excavated artifacts for Sear and Core. He also suspects Buric was involved in directing the unificationist turmoil and manipulating evidence to keep Breach from the initial murder inquiry, but these details remain his reconstruction. Buric openly boasts of removing artifacts from Ul Qoma while invoking Besźel patriotism and defying Breach, apparently to maintain the armed nationalists' support.

To unsettle the guards, Borlú declares himself Inspector Tyador Borlú of Besźel's Extreme Crime Squad rather than an agent of Breach. He accuses Buric of organizing Mahalia's murder and, crucially, of conspiring to murder Yolanda Rodriguez, a crime Borlú argues falls within Besźel's jurisdiction because the fatal shot was fired from there. When he attempts to arrest Buric, Buric draws a pistol on him. Ashil shoots Buric, who dies, and the two True Citizens fire on Ashil before retreating down the stairwell. Ashil's armor stops one bullet but he is also wounded below the shoulder. Croft rejects Breach's authority, invokes the potential response of his foreign government, and escapes by helicopter despite the lockdown.

While awaiting assistance, Borlú and Ashil question whether Buric had either the specialized archaeological knowledge needed to deceive Mahalia or the reasons to target Bowden at Copula Hall. Buric's death has not resolved who designed the Orciny deception. Ashil recalls that Bowden repeatedly denied Orciny's existence. As another Breach agent arrives to help him, Ashil authorizes Borlú's pursuit and gives him his Breach sigil and keys; Borlú also asks for his phone. The chapter ends before the new suspect is confronted.

After the rooftop shooting, a Breach agent attends to the wounded Ashil while Borlú collects his unfamiliar silenced gun and uses his sigil and telephone to leave Sear and Core. Borlú calls Qussim Dhatt and asks him to have David Bowden detained. Dhatt discovers that the officers assigned to protect Bowden were redeployed during the lockdown and that Bowden is missing. Border guards then recognize Bowden near Copula Hall but cannot tell whether he is occupying Besźel or Ul Qoma. He deliberately walks with gestures, dress and bearing that convey neither civic identity, so police trained to unsee the other city fear that watching or arresting him could itself constitute breach. His apparent neutrality may let him walk out through the otherwise closed borders.

Borlú asks Dhatt to go toward the border through Ul Qoma and telephones Lizbyet Corwi to approach through Besźel, guiding both by phone along overlapping streets. Neither is to approach Bowden unless he clearly identifies himself as being in that officer's city. Borlú makes his own way through the crosshatched Old Town, showing his temporary Breach sigil as needed. He reaches Dhatt, sees Corwi, and approaches Bowden, who continues his carefully ambiguous walk. He is holding a clicking, damaged Precursor mechanism and threatens Borlú with it. Borlú deduces that Bowden used the object to strike and kill Mahalia, and that its sharp parts caused some of her facial wounds. Bowden's guarded responses and admissions about the weapon and removal of the body substantiate key parts of the reconstruction.

Borlú explains that the elaborate Orciny deception required Bowden's historical expertise and was driven by a wish to make his discredited theory seem true, not primarily by the money Buric and Sear and Core could make. Bowden had presented himself to Mahalia as a skeptical academic while helping manufacture messages and evidence that persuaded her she worked for Orciny. Borlú believes Mahalia eventually saw through the claims but tried to warn Bowden, not knowing he had created the deception. Bowden indicates that he called Buric to arrange removal of her body and that an outdated map caused Yorjavic's intended estuary disposal route to end at the renovated skate park.

Borlú also accuses Bowden of telling Buric where Yolanda would be, even though she did not know the truth, and of arranging to appear among Yorjavic's intended victims to deflect suspicion from himself. These are Borlú's deductions during a confrontation, rather than an explicit full confession to directing every killing. He persuades Bowden to relinquish the Precursor object by offering him a genuine look at what exists between the cities. Bowden never chooses one jurisdiction, so neither Dhatt nor Corwi arrests him. Using Ashil's temporary authority, Borlú physically draws Bowden into Breach, where he is held without a conventional police arrest. Borlú realizes that the breach he has officially been investigating is still his own.

The Precursor mechanism Bowden surrendered disappears into Breach's bureaucracy, and Borlú never learns what it does or whether Sear and Core's technological interest was justified. In the aftermath of Riot Night, Ul Qoma maintains aggressive policing and announces a Vigilant Neighbours campaign, while Besźel's press and politicians largely avoid discussing the disorder. The Breach shutdown lasted thirty-six hours. The reported death toll is twenty-two in Ul Qoma and thirteen in Besźel, excluding refugees who subsequently died and people who disappeared. Foreign journalists try to obtain interviews with Breach, and both cities' unificationist movements have been greatly reduced.

Borlú spent the first day after bringing Bowden back confined in his cell, but his door has since been unlocked. Over three days after Ashil's release from medical care, they walk between the cities as Ashil trains him to navigate Breach less conspicuously than Bowden had. Ashil refuses to disclose where Bowden is being held. When Borlú observes that Bowden had never technically breached, Ashil acknowledges that Breach will have to submit paperwork to the Oversight Committee, then suggests it could invent or force a crossing and declare it breach. Thus Bowden's custody remains a question of Breach's power rather than straightforward legal proof. Mahalia's body has been returned home and her parents have held her funeral. Sear and Core continues operating in Besźel; its involvement is described publicly in vague terms, and there are rumors CorIntech might be sold.

Borlú finally asks about the consequences of his own breach. Ashil explains that the daily perceptual discipline of ordinary Besźel and Ul Qoman residents maintains the cities' separation, with Breach intervening only when necessary. Someone who has spent more than a moment in Breach generally cannot return to unseeing the other city. He reveals that Breach's avatars were not born between the cities: they were once citizens of one or the other, breached, and were subsequently recruited. For Borlú, the alternatives are recruitment and whatever sanctions apply to breachers. Ashil says his detective skills are valuable because Breach's methods need to change, but makes clear that Borlú cannot resume his old life.

Ashil prohibits direct farewells. Borlú writes short letters to Sariska and Biszaya that others deliver, then silently sees Dhatt in Ul Qoma and Corwi in Besźel. Each recognizes him but avoids crossing the perceptual and legal boundary to speak. Borlú accepts recruitment rather than the consequences of going rogue, reflecting that his role has changed from enforcing either city's laws to preserving the distinction that makes both legal systems possible. He signs off as Tye, a probationary avatar of Breach, and rejects the idea that his new life is only in neither city: he lives in both the city and the city.