Days later, with no word from Reyne, a frustrated Dior seeks out Joaquin. She confirms he is free from his thralldom and learns he has stayed behind for his beloved, Isla, a maidservant to Nikita. Promising to help Isla, Dior secures Joaquin’s loyalty for the planned rebellion. Later, Dior meets Reyne, who leads her through secret passages to a crypt beneath the holy Sepulcher of the Mothermaid—the holy tomb and vault housing the silver coffin of the Mothermaid, the holy mother of the Redeemer—which Celene’s mote cannot enter. There, Dior meets Reyne’s newly freed swordmaids: Lady Arlynn and the sisters Gillian and Morgana. Dior proposes a plan to exploit the vampires’ internal conflicts by assassinating Nikita and Lilidh. To expand their numbers, Dior provides more of her blood for the women to give to trusted allies. As they leave, Celene’s mote spots “the twin skulls of the Esana, etched in the clouds behind Michon’s raised sword. And between, the sigil of the Grail” hidden in a mosaic on the crypt wall (539).

Later, Dior stands by Lilidh’s side during a feast. Nikita’s daughter, Kiara, wins a duel against her cousin Alix, the Draigann, but is visibly upset by her father’s preference for his new fledgling, Aaron. Lilidh taunts Nikita about replacing Kiara with Aaron as his lover. The feast is interrupted when Nikita’s younger daughter, Soraya, announces a messenger at the gates. The entire court follows Nikita to the outer walls to investigate. From the battlements, Dior sees the indistinct outline of a legion of warriors ready to attack. She hears Gabriel’s voice in her ear, whispering, “And if God Himself should tear us asunder, if all the Endless Legion stood in my path, I would find my way back from the shores of the abyss to fight at your side […] I’ll not leave you, Dior” (546).

From the walls of Dún Maergenn, the court sees Gabriel de León at the head of a massive duskdancer army, with Phoebe á Dúnnsair beside him. Gabriel and Nikita trade insults, and Nikita reveals Aaron is his new thrall, which devastates Gabriel. Phoebe declares that the duskdancers are there to reclaim something the Dyvok stole, breaking their truce. 

After Nikita forces the army to retreat by hurling huge stones, he prepares his defenses, ordering all mortal thralls to the front lines. He violently punishes Kiara, whom Lilidh blames for the broken truce. Back in her room, Dior is horrified, realizing the thralls will be slaughtered. She asks Celene’s mote to go to Gabriel and convince him to delay the attack to give her internal rebellion time to succeed. Reluctantly, Celene agrees.

Celene approaches the duskdancer camp and, after a tense encounter with the guards, is brought before Gabriel. She relays Dior’s plan to free the thralls from within and asks him to delay his attack. Their meeting is interrupted when scouts bring in a captive: Nikita’s daughter, Soraya. She reveals she was sent to offer Dior to the powerful Voss vampires in exchange for their military aid. After extracting this information, Gabriel kills Soraya. Though he initially refuses to wait, Celene reminds him of his friends Aaron and Baptiste inside the fortress. Persuaded, Gabriel agrees to give Dior one day, but he forces Celene to remain in his camp as a hostage.

Dior and her conspirators gather in the crypt to plan the assassinations of Nikita and Lilidh. Needing silver weapons, they try to pry decorative silver swords from the Mothermaid’s tomb but fail. As Reyne pulls on the main effigy, she triggers a hidden mechanism that rolls the tomb aside, revealing a secret staircase leading deeper underground. Celene watches in mote form as the group descends, unable to cross the threshold herself. When they return, they’re deeply shaken by what they’ve discovered. Furious and determined, Dior announces she is going to find a saw to cut the silver blades free.

In his tent, Gabriel confronts Celene, revealing he knows his blood is now bound to hers. He accuses her of being an Ilon—a vampire who can manipulate emotions—and using that power to orchestrate his fall at the Cairnhaem bridge. Celene admits to it, explaining her desperation stems from the fact that her soul’s salvation depends on Dior. The argument shifts to their shared past, and Celene bitterly recounts a childhood promise Gabriel made to always protect her, a promise she feels he broke when he left home and never answered her letters.

Celene’s mote watches as Dior enlists Joaquin to create a distraction at the smithy, allowing her to steal an ironsaw for the silver blades. Reyne intercepts her, informing her that Nikita has demanded her presence at a speech to his court. As Reyne helps Dior dress, she explains her difficult past: Her father was a common wanderer who abandoned her royal mother, Niamh Nineswords, the sovereign of House Maergenn. As a result, Reyne was raised in exile and never accepted by her family. Dior comforts her, telling her that her own strength defines her, not her mother’s legacy. The two share a passionate kiss before heading to the hall.

Continuing their conversation, Gabriel asks Celene about his father. Celene reveals that when Gabriel was 12 and dying from the flux, their mother, Auriël, secretly performed a ritual to summon a vampire—Gabriel’s true father. Celene followed and witnessed Auriël beg him to save “our son.” He initially refused, but Celene emerged from hiding and threatened him until he relented, giving Auriël a cup of his blood that cured Gabriel. Gabriel learns he was saved by vampire blood and that their mother’s creed was “Famille is forever.” He realizes his father was from San Yves, the Esani stronghold, and deduces that Celene sought him out after being turned. Celene confirms it, revealing that Gabriel’s father was Wulfric, her own vampiric teacher.

In the Blackheart’s court, Dior’s plan to assassinate the Dyvok siblings unravels. Aware of the conspiracy, Nikita stages a cruel game, forcing the plotters—Maeron, Gillian, Declan, and Morgana—to attack one another. When Nikita commands Dior to execute Reyne, Dior realizes she has been discovered. She makes a desperate move, coating a sword with her own holy blood and striking at Nikita. He easily deflects the attack, injuring both Dior and Reyne. Lady Arlynn seizes the sanctified blade to continue the assault but is brutally killed by Nikita as her husband is slain in tandem by Aaron. Nikita executes the other wounded conspirators before Dior’s eyes.

The source of the betrayal is revealed to be Isla, who was never freed but has been Nikita’s loyal thrall all along. Just as she reveals her treachery, horns announce the arrival of Gabriel’s army. After a rousing speech to his court and a final assertion of dominance over his sister Lilidh, Nikita marches out to defend the fortress. 

The narrative returns to Celene and Jean-François, who bring a captive Gabriel into the cell. He intends to hear both siblings’ accounts of the ensuing battle to discern the truth. The chapter closes with Celene and Gabriel recalling how they both, uncharacteristically, prayed for Dior before the fighting began.