Gabriel and Celene offer Jean-Francois conflicting accounts of the three-pronged assault on Dún Maergenn. Celene describes her advance along the western seawall with Keylan á Meyrick, where they were met by Nikita Dyvok, Kiara, and Aaron de Coste. Using a powerful ability called the Dyvok Tempest, Nikita kills Keylan and his forces before shattering a section of the ancient wall with a single stomp. Nikita then leaps into the city to confront Gabriel. 

The fight splinters into three duels: Gabriel versus Nikita, Phoebe versus Kiara, and Baptiste versus his former lover, Aaron. Aaron cruelly taunts Baptiste, goading him into attacking and then springing a trap. To save Baptiste from being strangled, Gabriel throws his sword at Aaron, leaving himself defenseless. Nikita seizes the opportunity, striking Gabriel a destructive blow. As Nikita prepares to kill the downed Gabriel, Lachlan arrives, saving him with a last-minute blast of silver.

Lachlan’s arrival at the head of a silversaint army turns the tide of the battle. Lachlan shoots Nikita in the face, but Kiara defends her sire. In an act of cowardice, Nikita abandons Kiara and flees, with Aaron following behind. Gabriel and Lachlan reunite, and their combined forces secure the border of Dún Maergenn. Enraged by Nikita’s abandonment and cruelty, Kiara defies his order to bring him Dior. Instead, she kills Dior’s guards and frees both Dior and Princess Reyne, telling them to hide. Just as Gabriel’s army prepares to assault, the Voss army, led by Fabién’s children, arrives at their rear, trapping them. Gabriel realizes Fabién planned to betray Nikita all along, leaving Gabriel’s forces caught between two enemies.

As the battle for Dún Maergenn begins, Gabriel divides his forces, reluctantly allowing a wounded Baptiste to pursue Aaron. Celene joins Gabriel and Phoebe to confront the Terrors Alba and Aléne. Inside the Dyvok stronghold, Kiara’s escape with Dior and Reyne is cut off by Lilidh and Kane. In the ensuing fight, Kiara kills Kane and gravely wounds Lilidh but is severely injured. Reyne saves Dior with the Nineswords’ blade, but  Lilidh recovers and uses her Whip to command Kiara, brutally decapitating her. 

On the battlements, Lachlan’s silversaints are hampered by Nikita’s tactic of dousing them in prisoner blood to dull their aegis. Lachlan duels and disarms Aaron, but Baptiste tackles Aaron before Lachlan can kill him, and they both fall from the wall. During their fight, the Terrors physically torment  Gabriel and Phoebe. Enraged, Gabriel unleashes his power, boiling Alba’s blood as Celene bites Aléne. Their fight is halted by the arrival of a foulblood boy possessed by the spirit of Fabién Voss, the Forever King.

Facing off against the Terrors, Gabriel kills Alba as Celene kills Aléne. Speaking with Fabién’s voice, the foulblood reveals that Celene murdered their father, Wulfric, to steal his power. As this battle concludes, Baptiste manages to break Nikita’s thrall over Aaron, who finally defies his master. The distraction allows a wounded Lachlan to restrain Nikita, enabling Baptiste to kill the Blackheart with a silversteel hammer. 

Meanwhile, Dior and Reyne flee into an ancient crypt beneath the city, but Lilidh exploits an engraved invitation and manages to follow them onto the holy ground. Reyne wounds Lilidh with Dior’s blood but is critically injured in return. After Lilidh pins Dior to a statue, Lilidh’s wolf, Prince, who was released from his thrall when he bit Dior, attacks his mistress. Lilidh manages to snap Prince’s neck, but to save the drowning Reyne, Dior stabs Lilidh with her blood-coated sword, killing her. Gabriel arrives to comfort the traumatized Dior, whose blood revives Reyne. The chapter ends with the revelation that Prince is actually Connor, who stands up despite his broken neck.

Phoebe is joyfully reunited with her long-lost husband, Connor, who has been trapped in wolf form. This reunion, however, creates a painful, unspoken distance between her and Gabriel. Gabriel shares a tender moment with Dior, who calls him “Papa.” In the Redeemer’s tomb, Gabriel discovers what Dior and her friends found: Rather than saving humanity with his sacrifice as The One Faith teaches, the Redeemer cursed his five murderers to become the first vampires of the five bloodlines in an act of revenge. Enraged by this revelation and Celene’s deception, Gabriel attacks his sister.

As they fight, a charred Lilidh, who survived because her heart was removed long ago, emerges from the water and snaps Dior’s neck, killing her. Connor, in his wolf form, immediately kills Lilidh by tearing her head off, but she rips out his heart in the process, killing him as well. Connor dies as a man in a grieving Phoebe’s arms. A shattered Gabriel holds Dior’s lifeless body and sings a lullaby while Celene contemplates the complete failure of her plans.

Celene notes that Gabriel didn’t stay for Dior’s funeral. The Highlanders reckon with the losses of the battle. Lachlan á Craeg grieves his fallen silversaints—all of whom died in the battle. The children spared by Aaron’s mercy—Little Mila and young Joaquin—are found alive. Dior is laid in state in Amath du Miagh’dair, dressed by Reyne in platemail and threefold chain, her mangled hand exposed. Phoebe gives the eulogy beside Connor’s shrouded body. Celene tells Jean-François that Dior was “a girl I had cared for. A girl I had failed” (703).

Celene’s assertion that she had cared for Dior angers Gabriel, who attacks Celene before Jean-François can intervene. The siblings’ brawl ends only when the Chastain thrallswords drag her away. Bleeding, Gabriel vows to betray her to the Empress; Celene answers that he would sell heaven for a bottle and a whore. When he demands she die, she declares herself stone—the MOUNTAIN. Later, Jean-François asks why she endures. She replies, “Steel rusts. Ice melts. […] Stone endures” (705). As he departs, she whispers, “Tell Margot we will see her soon” (706).

After being punished for attacking Celene Castia, Gabriel is returned to his tower room. Jean-François confronts him, warning him never to harm Celene again, as she is the Empress’s property. Despite the admonishment, Jean-François is pleased with the night’s work, which will satisfy the Empress. He offers Gabriel one of his thralls to sate his vampiric thirst. Gabriel initially refuses but, struggling with his urges, eventually accepts the youngblood, Dario. Believing Gabriel will feed, Jean-François locks them in the room alone. The final moments reveal their true relationship: Gabriel and Dario are coconspirators. They recite a coded creed, and Gabriel addresses the youngblood by his real name, Joaquin. They affirm their shared secret mission: “For the Grail.”

Imprisoned in a dark cell, Celene, the Last Liathe, speaks to a spy in the form of a mouse named Marcel. She recounts the events that occurred after the funeral of the Grail, Dior. Celene explains that she waited in the crypt of Mother Maryn, where blood spilled on the tomb caused it to open. An ancient and immensely powerful vampire, appearing as a small child, emerged and attacked Celene, feeding on her to the brink of death. Celene identifies the vampire as Mother Maryn, the eldest surviving Esani. The feeding was interrupted when Maryn sensed Dior’s body in the tomb above. Looking up, Maryn recognized her, breathing the name “San Dior.” In the final moment, Dior, who was believed to be dead, opened her eyes.