The hunters arrive in Coste. A gendarme recognizes Aaron and summons his mother, the Baronne de Coste. The baron, whom Aaron has explained drinks heavily, treats Aaron with contempt, calling him “bastard” and the silversaints “halfbreed swine.” Aaron warns that an ancient vampire may threaten the feast guests. Despite his hostility, the baron grants them entry.

The baron outfits the hunters as servants. Gabriel serves drinks while the others patrol. Hours pass with no sign of Luncóit. Gabriel finds Aaron getting drunk and confronts him about neglecting his duties. When Gabriel claims Aaron is no different than the baron, Aaron reveals that his first love, Sacha, was a commoner killed by the baron after he found them together. Undeterred, Gabriel accuses Aaron of orchestrating the attack in San Michon that led to Sister Aoife’s murder. Before they fight, they sense the vampire’s arrival.

Marianne Luncóit materializes in the ballroom, an ancien of supernatural beauty. Talon orders the hunters to wait and follow Luncóit after she leaves with her intended victim, arguing that a direct confrontation would cause a massacre. A vampire named Adrien, who poses as Luncóit’s son, probes Gabriel’s mind and senses that something is wrong.

Luncóit enthralls Aaron’s cousin Véronique. Thinking of his dead sister Amélie, Gabriel defies orders and blocks the vampire’s path, his sevenstar blazing with holy light. Enraged, Luncóit flings Véronique aside and crashes through the windows. Greyhand and Talon pursue. A guard brings in the body of a serving girl Luncóit had already killed.

Outside, Gabriel rushes to help Aaron subdue Luncóit’s thrall. Talon appears and attacks Gabriel for disobeying orders, but Aaron intervenes, revealing that the thrall disclosed the place the vampires are staying. Greyhand spares Gabriel but tells him that he is no longer his apprentice.

The hunters raid an estate, finding dead servants. They learn from a thrall that Luncóit and Adrien are at Falls Bridge. There, they find Luncóit releasing white messenger ravens. She speaks of “the age of the fall” and prepares to fight as the hunters advance (448). As Talon and Greyhand battle Luncóit, Gabriel and Aaron manage to kill Adrien, wounding him and then pushing him into the river, which melts his flesh. Luncóit retaliates by ripping off Greyhand’s swordarm and ear and destroying his eye. As she taunts the three remaining hunters, Gabriel realizes their quarry is Laure Voss.

Laure reads their minds, taunting them with their past traumas; she claims credit for killing Amélie, mocks Aaron for blaming Sacha for their assignation, and tells Talon, “Thou art already ours, paleblood. They little Aoife could testify to—” (454). Enraged, Talon breaks formation, Aaron and Gabriel following. Laure mauls Talon and slashes Aaron’s face. As she tries to seduce Gabriel, he pushes his last silverbomb through a wound in her throat, engulfing her in silver fire.

Gabriel carries his companions to Coste Cathedral. A charred Laure survives, vowing vengeance before vanishing. Greyhand’s falcon brings a dead raven carrying a detailed invasion map.

The hunters return to San Michon, where Khalid commends them and announces Aaron is ready for sainthood. Gabriel is not expelled because the map gave the empire crucial intelligence: Voss intends to invade via Avinbourg.

That night, Gabriel visits Astrid and Chloe. Astrid gives him a letter from his mother, who promises to explain Gabriel’s heritage in person if he visits her at Firstmas. Astrid and Chloe then reveal that they discovered the fifth vampire bloodline when they accidentally dripped blood on a book, unlocking hidden text that describes Esani, the Faithless, as “sorcerers and cannibals, damned even among the damned” (466).

Leaving the library, Gabriel again sees Aaron sneaking from the Barracks. He follows him to the Armory, where he discovers him in a passionate embrace with Baptiste Sa-Ismael. A furious Aaron attacks Gabriel, but Baptiste intervenes, and Gabriel vows to keep their secret. Baptiste tells him he has a “lion’s heart.”

San Michon prepares for war. The day before the empress is scheduled to arrive, en route to Avinbourg with the imperial army, Gabriel receives his next aegis piece from Astrid. At a feast for Aaron that night, Empress Isabella arrives early and inspires the silversaints. However, Greyhand interrupts the festivities to argue that the plans centering on Avinbourg were likely a misdirection; the real target is probably Charinfel. Gabriel convinces the empress to send the initiates, led by Greyhand, to defend Charinfel as a contingency plan.

That night, Gabriel goes to the Library to say goodbye to Astrid. Fueled by vodka and the prospect of battle, their flirtation escalates into a passionate encounter, which is interrupted by alarm bells.

As Astrid hurries back to the Priory, Gabriel emerges to find a mob outside the Armory. Seraph Talon has caught Aaron and Baptiste together and denounces them as oathbreakers. Abbot Khalid arrives. Baptiste tries to claim sole responsibility, but Aaron refuses to let him lie, declaring that their love is “no fucking sin” (498). As violence threatens, Greyhand fires his pistol and demands that Aaron be judged by the Order’s laws. Khalid agrees and has him and Baptiste imprisoned.

After the crowd disperses, Greyhand tells Gabriel that Aaron’s aegis will likely be flayed from his skin and that both he and Gabriel will be expelled. When Gabriel suggests that it is unfair that Aaron alone will not be riding to battle, Greyhand says that Gabriel will not go to Charinfel, reminding him that he is no longer his apprentice. Greyhand strikes Gabriel, berating his arrogance, and then tells him to choose whether he will be a man or a monster.

Four days after the forces depart, Gabriel remains at San Michon, furious at being left behind. Aaron and Baptiste are imprisoned. Consumed by rage, Gabriel studies the captured vampire map. When he punches the wall in frustration, some of his blood soaks the paper, revealing a riddle that concludes with an invitation to “dance” “through blood and fire” (504). That night, Gabriel shows Astrid and Chloe how his blood activates the secret message. Together, he and Astrid deduce that Avinbourg is a feint and that the riddle references mountain passes named after angels. He identifies the “Twins”—Mont Sanael and Mont Gabriel, angels of blood and fire—as the Forever King’s true crossing point. Realizing only the undead could survive the crossing, Gabriel resolves to stop them.

Two hours later, a small company assembles: keepers, blackthumbs, grooms Kaspar and Kaveh, and the freed Aaron and Baptiste. Gabriel dispatches the grooms as riders to alert the main armies. The sky platform descends with Prioress Charlotte, Chloe, Astrid, and two dozen armed sisters of the Silver Sorority, who will join the fight. Gabriel confronts Astrid about the risk, but she says that if this ends badly, it will at least free her. Gabriel rallies the company of 50, and they ride west into brutal winter conditions that force several to turn back or remain where they are.

On the 13th day, the remaining company reaches the pass between the mountains and shelters near two watchtowers. A lightning flash reveals thousands of vampires ascending the pass.

Speaking to the others, Gabriel calls this their moment of heroism. He orders Charlotte to form a firing line while two brothers plant ignis charges to trigger an avalanche. Gabriel and Aaron strip to their silver-clad torsos and charge down toward the Dead, accompanied by Baptiste. Their glowing aegis tattoos create a protective circle. As they slaughter the horde, both Aaron and Gabriel sense Fabién Voss in their minds. Gabriel then hears Astrid scream and turns to see Laure attacking the blackthumbs near the charges.

Gabriel races back up the slope to find the blackthumbs losing to Laure. He screams warnings to Charlotte and Astrid and then confronts Laure. His sword is useless against her flesh. A volley from the sisters staggers her, and Gabriel drives Lionclaw through her chest, but she pulls it free and kills Charlotte with it. Gabriel tackles Laure to protect Astrid. While strangling him, Laure reveals that she massacred Lorson, killing his mother and sister. Enraged, Gabriel grabs her throat. The word Esani rings in his mind as his bloodgift activates, boiling Laure’s blood and reducing her to ash. He hears the Forever King’s roar of rage. Gabriel lights the ignis fuse and races for a tower as the explosion triggers a massive avalanche, burying the legion.

Gabriel rides to Lorson with Aaron, Baptiste, and Greyhand, who arrived at the pass shortly after the battle, along with the main armies. They find Lorson burned and lifeless. Gabriel finds Celene’s charred remains in the ruined chapel and his mother’s body in their yard.

As soldiers build pyres, Greyhand comforts him, and Gabriel vows to avenge his family. Aaron and Baptiste, whose love is still condemned by the order, decide to leave together. Before departing, Aaron warns Gabriel about Seraph Talon, whom he suspects read his mind to discover his meeting with Baptiste.

Back in San Michon, Gabriel is inducted into the order of silversaints; he is also knighted by Empress Isabella, becoming a Chevalier of Elidaen. At the feast, Isabella summons him to the Library. She questions him about discovering the Forever King’s plan, and he recounts the events, omitting Astrid’s and Chloe’s roles. Isabella confirms that a multi-front war against the other vampire houses has begun and tells Gabriel that she will soon call upon him.

As he is dismissed, Gabriel asks that Astrid’s exile be ended. Isabella is displeased but grudgingly approves. However, she warns him that her mercy has limits.

That night, Gabriel waits in the Library for Seraph Talon. He accuses Talon of setting a trap for him and Astrid, as he did with Aaron and Baptiste. He also accuses Talon of murdering a serving girl in Coste and feeding on Sister Aoife, who was pregnant with his child; her meeting with the groom was an attempt to secure herbs that would result in an abortion.

Talon confesses his struggle with the sangirè, which he angrily claims Gabriel is too young to understand. He also admits that he killed Aoife and their child but calls it “mercy.” Gabriel calls him a coward. Enraged, Talon attacks and bites Gabriel’s throat. Greyhand arrives just in time to kill Talon; Gabriel previously spoke to him of his suspicions. As Greyhand helps the wounded Gabriel, he says that life is a story and that Gabriel must choose whether his will be that of a monster or a man.

Later, Gabriel awakens in the Infirmary to find Astrid at his bedside. She is furious that he petitioned for her freedom; she no longer wants to leave because she has fallen in love with him. Unable to deny his feelings, he gives in to passion. At the height of their intimacy, Astrid begs Gabriel to bite her. He surrenders to his vampiric hunger and bites her breast, drinking her blood as they reach climax.

Afterward, they acknowledge that their love is a sin but decide to continue their relationship in secret until the war is won, vowing to be together forever once their obligations are fulfilled.

In the present, Jean-François summarizes the next five years: Gabriel became a legendary warrior known as the Black Lion. The historian demands to know how it “all [came] undone” (550). Gabriel reveals that he and Astrid loved in secret for five years. Despite their caution, Astrid became pregnant, and they were excommunicated and cast out. Their daughter, Patience, was born human, becoming Gabriel’s reason for living. Overcome, Gabriel refuses to speak further. Jean-François insists. Gabriel shatters his wineglass in his hand. The blood causes Jean-François to recoil. Gabriel proposes returning to the story of the Grail. As the thrall Meline bandages his hand, Gabriel prepares to continue.