Dark Age

Dark Age opens with the Solar Republic reeling from Atalantia au Grimmus's destruction of the White Fleet over Mercury. Darrow reaches the trapped Free Legions too late to prevent the disaster but rescues the tortured Orion and tries to turn the siege against Atalantia through Operation Voyager Cloak and a hidden network of ancient Storm Gods. Atlas au Raa defeats the original trap by using buried hardlines to overload mining-city reactors and collapse most of the northern shield chain. In the battles that follow, an omega atomic destroys Red Reach and most of the Second Army, while Darrow uses Orion's engineered storms to isolate and maul the first Society landing waves. When Orion deliberately drives the weather system toward a planet-devastating horizon, Darrow uses his master override to sever her from the Storm Gods, killing her and stopping the escalation. The Free Legions later survive Atlas's capture of Darrow and defeat Ajax's assault on Heliopolis, but millions are dead or missing, radiation and supply shortages tighten the siege, and Atalantia gives them an ultimatum. Virginia's secretly launched supplies let the army endure, while Harnassus and Darrow reject a Senate order to surrender.

On Luna, Virginia au Augustus tries to assemble the Senate votes and military authority needed to rescue Mercury while also fighting the Syndicate network that abducted Pax and Electra. She reconciles with Dancer after proving that his partner was the Duke of Hands, and Dancer agrees to support the rescue. The Senate session instead becomes the Day of Red Doves: Dancer is killed, Daxo dies defending Virginia, Lilath is revealed as the Syndicate Queen, and the Republic government collapses into a coordinated coup. Virginia survives imprisonment and the Pandemonium Chair by using false memories and neurological defenses, then discovers that Lilath carried a clone of Adrius au Augustus created from instructions left by the original Jackal. The clone, whom Virginia calls the Abomination, claims responsibility for the coup, holds Sevro and other Howlers, and threatens to erase Sevro's family memories. Virginia poisons the clone, wounds Lilath, and escapes through the Black Cathedral network, but Kavax forces her to abandon an immediate rescue attempt. Learning that the Rim has allied with the Core and that Mars is the remaining defensible center of the Republic, Virginia orders a retreat there.

Ephraim ti Horn survives the uncontrolled shuttle crash that ended Iron Gold but loses a leg and becomes a captive of Sefi's Obsidians on Mars. Sefi hires him to train the skuggi in infiltration and intelligence work while pursuing an independent Obsidian state. Ephraim grows closer to Pax and helps Sefi seize the Cimmerian helium mines, but the arrival of Volsung Fá fractures the Alltribe. Fá kills Freihild, Sefi reveals that Volga is Ragnar's biological daughter and intended heir, and evidence later shows that Xenophon has been working for Atlas and that Fá is a Gorgon asset planted among the Ascomanni. After helping Pax and Electra escape and then joining the rescue prompted by Lyria's broadcast, Ephraim returns to Olympia to expose Xenophon. Xenophon frames his actions as a coup, Fá takes control of the male warjarls, defeats and kills Sefi, and sacks Olympia. Ephraim uses a heartspike that Pax secretly packed with explosives to kill Xenophon, but Fá survives the blast, tears out Ephraim's heart, calls him worthy, and kills him.

Lyria of Lagalos is imprisoned by Victra after Iron Gold because the unauthorized device she carried helped enable the kidnapping of Pax and Electra. A Red Hand crisis intersects with the attack on Victra's ship, the Pandora, when Lyria and Volga encounter Figment, an operative carrying advanced internal technology. During their escape, Figment dies and a metallic organism transfers into Lyria, identifying her as the new Figment. Lyria, Volga, and the pregnant Victra survive a crash in Cimmeria, but Red Hand forces later capture Victra and Volga and murder Victra's newborn son Ulysses. Lyria infiltrates the Red Hand as a prospective childwife, arms captive girls with artificial acid teeth, frees Victra, and helps break the Red Hand's control of the mine. Harmony dies in a pit of pitvipers, and Lyria's broadcast draws Ephraim, Pax, Electra, and a broad Martian civilian response. After Ephraim's death and Ulysses's burial, Fá offers to leave Mars and release captives in exchange for Volga. Victra reveals that Volga is Ragnar's daughter; Volga chooses to go with Fá, intending to get close enough to make him pay. Pax then tells Lyria that Virginia is alive, reveals that he has learned more about her Figment implant, offers help finding Liam, and directs her attention toward a place called Oculus without claiming to know the implant's full origin.

Lysander au Lune arrives at Mercury with Diomedes and Seraphina after the Rim acts on the alliance policy proposed at the end of Iron Gold. He helps persuade Atalantia to negotiate with the Rim and joins the Iron Rain to earn a Peerless Scar, but Darrow's Storm Gods devastate the landing and Darrow defeats Lysander in the desert. After Seraphina is killed and Lysander becomes separated from the Society army, Apollonius approaches him about a possible alliance, which Lysander initially rejects. Atlas later recognizes Lysander and reveals Atalantia's planned chemical destruction of Heliopolis. Under the false identity Cato au Vitruvius, Lysander allows Atlas to be captured, returns Alexandar to Darrow, and gains access to Glirastes. He turns Glirastes and Heliopolitan loyalists against the Republic, kills Alexandar when Alexandar discovers him, and uses the Republic's own EMP project to black out Heliopolis. Lysander rallies the freed prisoners and Praetorians, leads the powerless city's counterattack, wounds Darrow in a cavalry pass, and helps bring about the fall of Heliopolis. Cassius then appears alive aboard the Archimedes and extracts Darrow, proving that Diomedes's earlier report of Cassius's death was false.

After the Long Night, Atalantia gives Lysander his Peerless Scar while privately preparing to have him assassinated. Lysander avoids the immediate threat by proposing a political marriage that would make Grimmus and Lune publicly indivisible, then becomes Atalantia's lover. The dying Kalindora subsequently reveals that Lysander's parents had joined a coup against Octavia, that Octavia ordered their deaths, and that Kalindora and Atalantia planted the bomb that killed them. She also reveals that Octavia used the Pandemonium Chair to erase Lysander's memories of his mother. Lysander conceals what he has learned, remains outwardly aligned with Atalantia, and later forms a secret pact with Apollonius, offering him Atalantia, Ajax, Atlas, Darrow, and instruction in the Mind's Eye in exchange for his blade and strategic support. Meanwhile Virginia returns to a Mars that rallies around the Republic, reconciles with Victra, and learns that Earth has fallen to combined Rim and Society forces. The final image is Lysander and Apollonius among the restored statues of the old Sovereigns, whose outstretched arms point together toward Mars.