In the crawlspace under the Crone Witch Elowen’s home, Zevander Rydainn holds Maevyth back from her comatose sister, Aleysia. Maevyth killed Elowen; now, the house is surrounded by spider-like creatures—humans infected with a new pestilence. Knowing that Aleysia could be infected, they put her on Elowen’s bed. Zevander is running out of vivicantem, a mineral powering his magic. Zevander keeps watch; the scar on his face grows as his magic powers weaken.

Maevyth dreams of walking through a dark forest, in which a dying child tells her that only death can save them. The roots of trees wrap around her and strangle her. She wakes to find that Aleysia’s eyes have turned black. As the infected Aleysia strangles Maevyth, Maevyth reaches out with her blackened fingers, begging Aleysia to stop. Morsana, the goddess of death, urges Maevyth to kill Aleysia.

The narrative flashes back several centuries to Zevander’s young adulthood. Zevander and his father, Lord Rydainn, go to the Black Salt Tavern in Costelwick. Lord Rydainn confronts a hooded woman, demanding a cure to Zevander’s sablefyre curse. He wants to find Cadavros, the disgraced mage who threw an infant Zevander into the fire and tried to consume him whole. Two guards take Lord Rydainn and Zevander into custody. The woman demands to keep Zevander, revealing her scarred face. The guards take Zevander and Lord Rydainn away on orders from the king.

Back in the present, when Maevyth wakes up, Aleysia is sleeping. Morsana’s voice again tells her to kill Aleysia, but Maevyth refuses. Zevander enters, but Maevyth chooses not to tell him about the dream. Zevander notes that Aleysia cannot cross the Umbravale into Aethyria. Maevyth decides to sleep outside the bedroom and asks Zevander to lie down with her. Zevander explains a scar on his chest, which is the mark of sablefyre.

Since Cadavros wants Zevander as an ally, Zevander and Maevyth worry that he might join against his will. Moreover, Cadavros is bound to Prince Dorjan, the son of King Sagaerin of Nyxteros. If either Dorjan or Cadavros dies, the other dies, too; if Dorjan dies, the deadly Black Pestilence will sweep across the world.

Zevander tries to seduce Maevyth, but when she turns him down and reminds him of Aleysia’s presence, Zevander gets angry, thinking that Maevyth is calling him sexually unseemly. Explaining that he has misunderstood, Maevyth attributes his overreaction to the fact that he has experienced sexual abuse.

In the past, Zevander and his father find Zevander’s mother and Lord Belthane, King Sagaerin’s advisor, in the throne room. Belthane explains that Lord and Lady Rydainn contracted Cadavros to protect them from the Solassions in exchange for a sample of Zevander’s magic, violating the Nyxteros law against demutomancy, or blood magic. Lady Rydainn begs the king to pardon her husband, but Belthane then accuses Lord Rydainn of murdering a Solassion woman. In response, King Jeret of Solassios suspended trade of dragoniron, a metal used to make weapons. Lady Rydainn is disgusted with her husband for this betrayal; she stops him from explaining himself. Instead of imprisoning Lord and Lady Rydainn, Belthane takes Zevander and his father into custody. They are sent to the Cinderbone Mines in Solassios.

In the present, Zevander realizes that he must have hallucinated Maevyth insulting him. Lack of vivicantem causes a condition called malvicantem, which comes with worsening mental health, cravings for flesh, and death. Zevander has no intention of leaving Maevyth since she’s his fated mate. He investigates the crawlspace where they found Aleysia, noting that it’s too cold for a mortal to withstand. He finds a black stain that fades into the wood when Zevander looks at it. There are also scratch marks, like something tried to claw its way out.

Maevyth asks if Zevander is still upset and suggests sleeping in separate rooms. Zevander, hurt, says that he intends to keep watch. He asks how Maevyth knows Aleysia is not the demonic wrathavor, which earlier consumed and took the form of Moros, the man Maevyth was once condemned to marry. Maevyth would notice if Aleysia were not herself.

Zevander feels a sharp pain in his chest; he focuses on the scorpion necklace that Maevyth wore during the Becoming Ceremony, which causes the pain to recede.

In the past, Zevander and his father cross the Solassion desert in a line of prisoners chained to one another. As a man behind Zevander collapses with sun poisoning, Lord Rydainn explains how the moons in Nyxteros protect the Lunasier like the Rydainns—mancers who get their power from the moons. The dead prisoner’s chains have seared his skin. The orgoth prisoner chained behind him, an orc-like humanoid with horns and tusks, splits the dead man’s skull, allowing the chain to come free.

At the mine, Zevander is separated from his father, but he doesn’t care after learning about his father’s crime. Zevander and the other imprisoned adolescents are brought to a closed door, behind which they hear screams. Four Bellatryx—elite, female Solassion warriors known for their sadism—enter the mine. Zevander tries to run, but a Bellatryx kills another teen in front of him. A guard punches Zevander, knocking him unconscious.

Zevander wakes up in Caligorya, a shadow realm of the psyche. An old man greets him. Sigils form on Zevander’s arms and neck, unlocking his ability to use magic for the first time. Zevander has always thought he was a spindling, or a mundane person, but the old man claims that Zevander is imbued with an older form of magic: The chaos god Deimos lives inside Zevander.

Zevander wakes up chained; a guard whips him. He laughs, thinking that a god is imprisoned within his fragile body, but the guard takes his laughter as provocation. The Bellatryx tells the guard to stop and send Zevander to the mines. Once Zevander is stronger, she wants him sent to her.

In the present, Maevyth and Zevander practice her magic outside during daylight, when the infected creatures are dormant. They flirt, and Maevyth debates whether she should give in to her desire for Zevander. She tries casting her bone-whip glyph but produces only a limp pile of bones. Suddenly, two creatures attack from the woods. Zevander suspends them in the air, but Maevyth fails to conjure her whip. Zevander encourages her to let go of her empathy and picture what the creatures would do to Aleysia. Maevyth kills one creature with her whip, but the other turns on Zevander, who refuses to use his magic. Maevyth casts another whip at the last moment, saving him. Maevyth sees a vision of her dead uncle Riftyn, which startles her.

Maevyth bathes Zevander with a cloth, noticing a red patch around his neck—the result of the creatures’ acidic saliva. Maevyth asks to train without risking Zevander’s life. She will think of the creature striking at Zevander, and the feeling of wanting to kill it, to cancel out her empathy.

The narrative flashes back to four days ago. Kazhimyr and Ravezio are chained in a dungeon while Captain Zivant, head of King Sagaerin’s guard, tortures them. Through Nilmirth, a truth serum, Zivant has learned that Zevander did not kill Dolion. Zivant demands to know where Dolion and Zevander have gone. Kazhimyr refuses to answer.

The torture is interrupted by a cupbearer announcing that King Jeret of Solassios has kidnapped Prince Dorjan of Nyxteros. Zivant leaves. Ravezio tricks the cupbearer, kills him, slips his chains, and frees Kazhimyr. As they flee, they overhear Zivant talking to Belthane. King Sagaerin wants to send men after the kidnappers, but his soldiers are busy quelling a riot of non-magic users outside the castle. Zivant sends a few men to pursue Jeret. Belthane reminds him that Sagaerin promised to help Jeret defeat the mercenary leader Kael Vexmoor. Zivant knows that Jeret is only provoking Sagaerin and will not kill Dorjan, and he is confident that Vexmoor is after Jeret, not Sagaerin. Upon hearing that Kazhimyr and Ravezio escaped, Zivant orders their crucifixion.

In the present, Maevyth is distracted from reading Elowen’s spellbook by Zevander, shirtless, repairing the roof. She notes a torture scar, but she’s aroused by Zevander’s body. Zevander notices and makes her admit it, acting offended and leaving. Maevyth spies on him masturbating while his prodozja, a spectral scorpion, stings his back.

When he returns, Maevyth asks about the scorpion and confesses that she wants to have sex with him. The sight of Maevyth reading arouses Zevander. Zevander doesn’t believe in enduring love, comparing love to a storm over an abyss of disappointment. Maevyth asks if he rejects the idea of fated mates, but he dodges the question. Maevyth thinks that love is worthwhile even if it ends in disappointment.

In the past, Zevander, now a strong, young man, works alongside Kazhimyr and Ravezio in the mines. Zevander recognizes the man pushing the water cart as his father, withered and gaunt. Warden Vicarek yells at the men to keep moving, but Zevander’s father gives him double his usual portion of water. Zevander promises to give his father some bread tomorrow.

At night, Zevander, Ravezio, and Kazhimyr reminisce about the Winter Somnial, a time of celebration in Nyxteros. They fantasize about women, but the warden interrupts, ordering two guards to grab Ravezio and making discriminatory remarks about Ravezio’s race. Ravezio is an Eremician, with lizard-like features and scales. When the warden plucks scales from Ravezio’s arm, Zevander threatens to kill him. The warden decides to force Ravezio to fight in an arena for the guards’ entertainment, but Zevander demands to take his place. The warden agrees. If Zevander wins, he will leave Ravezio alone but will torture Zevander’s father to death.

In the present, as Maevyth tries to wake Aleysia, she discovers a black mass with veins spreading on Aleysia’s side. Morsana’s voice urges Maevyth to kill Aleysia, but Maevyth stops herself. Aleysia says Maevyth’s name, but Maevyth isn’t sure if she hallucinated it. Maevyth finds the whistle she used to call Raivox, her draconic Corvugon, in Zevander’s clothes, but it’s melted.

Maevyth goes out to find Zevander and finds his shirt on the ground outside the archway into the Eating Woods. She hears someone calling her name but reminds herself not to trust what she hears in the forest. She finds Zevander at the Umbravale, murmuring something in Primyrian, an ancient language. He attacks her, his eyes completely black, but quickly snaps out of his trance, apologizes, and translates the Primyrian as “burn it down” (112). Maevyth tells Zevander about Aleysia, Morsana’s orders, and the black mass, which makes Zevander think that the curse on Aleysia is weakening. Maevyth compares the black mass to Zevander’s scar; she thinks of his scar as a symbol of his resilience. She shows Zevander the melted whistle, and his sablefyre accidentally melts it further into a bloodstone. Zevander needs to find vivicantem, and Maevyth suggests searching Moros’s home.

Kazhimyr and Ravezio escape and head toward Castle Eidolon. They encounter soldiers, whom Kazhimyr halts with a blast of freezing magic and Ravezio turns to stone with his gaze. Kazhimyr recognizes one soldier as the man who punished him before he was sent to the Solassion mines; he disables the soldier, leaving him to be consumed by a nearby beast.

Castle Eidolon is empty. Zevander’s older brother, Branimir, hidden in his cell, reluctantly admits that he’s not worried about soldiers coming to the castle. A spider attacks Kazhimyr, who reminds Branimir that they swore an oath to protect Zevander’s family. Branimir reveals that Dolion and Zevander’s sister, Rykaia, are going to Calyxar, home of the Elvynirans, an elf-like people who manipulate glyphs without blood magic.

Zevander examines the mass on Aleysia’s side; it’s like his scar, but his father never confirmed that Zevander’s scar was the result of sablefyre. Since vivicantem reduces Zevander’s scars, Maevyth reasons that they should go to Moros’s, find vivicantem, and give some to Aleysia as well. They see black claw marks under the bed and pieces of flooring under Aleysia’s fingernails. They bind Aleysia to the bed to prevent her from hurting herself.

The bloodstone made from Maevyth’s whistle melts into hot silver that flows onto the scar on her arm. It forms a glyph in the shape of a bird. When she tries to speak, a whistle comes from her throat. Zevander explains that the whistle has merged with her, so she will make that sound when she thinks of the glyph. Maevyth laments that her powers are comparatively inconvenient: deadly fingertips, a bone whip, and a whistle. She and Zevander laugh and reminisce about Aethyria.

In the past, Zevander, Ravezio, and Kazhimyr eat slop. Zevander only gets one piece of bread, which he saves for his father. Ravezio suggests asking Jagron, the guard overseeing them, for help. Jagron gets additional privileges for the additional ore Zevander mines. Kazhimyr tells Zevander to win his match in the arena.

When Zevander brings his father bread, Lord Rydainn says that he has heard about Zevander’s upcoming fight. He tells Zevander to win and suggests that he access the power of sablefyre despite the restrictions placed on the prisoners. Zevander’s father was once a Hexman, or a hunter of demutomancers; he was hired by Lord Vanhelm, a Solassion trader, to find his wife. When Lord Rydainn found Lady Vanhelm, she was hiding two children under a spell of silence. Thinking that she was abusing them, Lord Rydainn mortally wounded her. Lady Vanhelm told him that the children were the result of King Jeret sexually assaulting her. Lord Rydainn hid the children, gave the woman a funeral, and lied to the Solassions, saying that he had killed her. Lord Rydainn laments that he will never see his wife again and regrets contacting Cadavros for help.

In the present, Zevander pauses on his way to go hunting, distracted by Maevyth sleeping. General Loyce, Zevander’s former abuser and a leader of the Bellatryx, appears in his mind, telling him that he’s unworthy of love. Zevander notices that he cut himself without realizing; he leaves to hunt.

In the woods, Zevander is tracking a rabbit when a voice distracts him, speaking in Primyrian. He sees a shadow and follows it until the voice calls him again. Zevander finds himself surrounded by darkness. A tree appears before him, opens, and lets out two massive spider legs. Zevander turns away, dizzy and wobbling, and sees the rabbit again.