Xül confesses that he wants Thais and challenges her to deny that she wants him, too. She reminds him that gods are forbidden from having sexual liaisons with mortals, but he says that tonight is different. Suddenly, Thais hears Xül’s voice warning her, “This is the third trial, Thais. Get out of there NOW” (451). She realizes that the figure before her is only an illusion and runs from the room.

Thais races through the palace, which is now on fire. She passes the remains of contestants who gave in to their desires and were immolated. When her desires conjure an illusion of a dead Olinthar, she fears that her secret has been revealed, but she forces herself to continue.

Thais rescues Thatcher from burning to death and finds Kyren and Marx. Kyren saves the life of a contestant who is transfixed by an illusion of his dead wife, and the man lashes out in his grief and kills him. A message appears that says, “WHEN HEAVEN FALLS, ONLY THE SKY REMAINS” (456). Thais, Thatcher, and Marx decide this means that they must leap into empty air. Holding hands, they jump into the abyss.

Thais, Thatcher, and Marx land unharmed. Only six other contestants survived. Syrena, the Aesymar of Dreams and Illusions, and Pyralia, the Aesymar of Fire and Passion, explain that they designed the third Trial to test the contestants’ self-restraint. Thais, Thatcher, and Marx reunite with their mentors, and Thais is devastated that Xül won’t even look at her. During a brief moment alone with Thais, Nyvora reveals that only the contestants could see the illusions, but the divine spectators heard everything. Nyvora says that Thais is “delusional” to think that Xül could ever want her, but Thais retorts that Nyvora wouldn’t feel so threatened if that were the case. Back at the Bone Spire, Thais cries alone in her room.

The narrative moves to Thatcher. Chavore explains that none of the mentors knew the so-called ball was really a Trial, and he invites his mentee to open up about what he experienced. Their conversation turns to the concept of divine couples, and Thatcher discovers that Chavore has no memory of their visit to the volcanic cavern.

Chavore scathingly describes how the Twelve arrange unions among themselves and their offspring to produce “chess pieces” and opens up about how he’s never felt like he’s good enough for his father. Although Thatcher feels sorry for his half-brother, he reminds himself that the god is “part of the system that had destroyed everything [he] loved” (475).

The narrative returns to Thais. The morning after the third Trial, she seeks out Marx’s company. They speak of Kyren and the times their fallen ally saved their lives. Thais reveals to Marx that Olinthar is her father and that Thatcher has Primordial power. Marx teases her about her attraction to Xül but doesn’t pry. Thais resolves that she’ll have to speak to Xül.

Thais goes to Xül’s study and apologizes for what happened during the third Trial. However, he blames himself because he kissed her and flirted with her. He tells Thais that he’s wanted her ever since she came to the Bone Spire but that they can’t be together. She kisses him anyway.

Thais wants to have sex with Xül. Although he shares her desire, he offers a compromise. Instead of touching her, they watch each other touch themselves. Xül says that they cannot do this again.

The final Trial will be overseen by Vorinar, Aesymar of Fate, and Aella, Aesymar of Chaos. Xül brings Thais to a seer named Heron, who is Vorinar’s mortal son and lives in the mortal world. Because Heron is blind, his father hid him so that he wouldn’t be forced to undergo the Trials. When they request Heron’s advice regarding the fourth Trial, he warns Thais that she may discover truths that she isn’t ready for unless she’s careful.

When Xül steps outside for a moment, Heron tells Thais that he can see the thread of her fate stretching on for centuries but that Thatcher’s thread ends with the Trials. He tries to ease her distress by saying that fate can be changed. She resolves to do whatever she must to keep the future Heron saw from coming to pass.

Xül brings Thais to the Village of Mireen, where his mortal relatives are preparing to celebrate the summer solstice. They give her a warm welcome, and she marvels at how different the lighthearted version of Xül chatting and laughing with his family is from the aloof god he is in Voldaris. That night, she longs for what the two of them could have been to each other if their fates were different.

On the evening of the solstice, Thais joins Xül and the villagers in a ceremony where they light candles to express their wishes. Her wish is for Thatcher’s safety. Xül invites her to dance and then takes her on a boat ride to a secluded pool. He opens up about the pain of feeling like he doesn’t fully belong anywhere and of watching his mortal relatives die. He confesses that his feelings for Thais are deeper than physical attraction but adds that he doesn’t think he deserves her because he’s keeping secrets, is bound to his duty, and is engaged. She answers, “Whatever this is, whatever it costs, I want it” (529). They kiss, and he opens a portal to his bedroom in the Bone Spire.

As Thais submits to Xül sexually, she is finally able to let go of “the exhausting need to anticipate every threat” she’s carried all her life (536). Afterward, he massages her with healing balm. When he voices his concern that he was too rough and possessive, she assures him that their encounter was everything she wished for. They fall asleep in each other’s arms.

The narrative shifts to Thatcher. Olinthar invites him to his realm for the third time that week and brings him to a dungeon where a spy from Draknavor is being held prisoner. Olinthar tortures the spy, saying, “This is the fate that awaits any enemies of my realm” (548). When the prisoner begs Thatcher to end his suffering, he unleashes the hatred he feels toward Olinthar to obliterate the spy. Olinthar praises his power as well as his compassion. Elysia escorts Thatcher back to Bellarium and defends Olinthar’s actions.

The narrative returns to Thais. Xül prepares breakfast for her and then leaves on urgent business. While looking for clues about the fourth Trial, Thais finds a letter hidden in Xül’s study that reads, “The male Morvaren is our primary concern. He must be eliminated in the final trial” (562).

Thais confronts Xül and demands answers about the plot to kill Thatcher. Her power reacts to her rage, and she forms a star-sword without consciously deciding to. When she advances on Xül, Aelix knocks her unconscious.