Harlow sneaks back into the unusually quiet Carrenwell family home and hears screaming. She investigates and finds her older brother, Able, in the midst of a paranoid episode, ranting about Drained in the walls while being restrained by guards. Her sister-in-law, Sierra, has fresh bruises on her neck. After a healer sedates Able, Harlow’s parents, Harrick and Liza, dismiss the guards and reveal the truth: They believe Able is going mad.

They suspect the depletion of the family’s magical well is the cause, as Abel’s condition has worsened with his increased use of it to power the city’s defenses. This news makes Harlow’s mission to Mountain Haven even more critical, as the family’s power is now unstable. Back in her room, Aidia, appears, looking bruised and exhausted; it is clear that Rafe beat her up again. She has come to say a secret goodbye before Harlow leaves. Aidia refuses to let Henry heal her, urging Harlow to save his magic for her own dangerous journey. They share a tender farewell before Harlow falls asleep.

As Harlow prepares to depart from Lunameade, Kellan pulls her aside with a dire warning. He reveals that the Havenwoods may believe that Harrick was responsible for the Drained attack that destroyed Mountain Haven ten years prior by deliberately diverting the horde away from Lunameade to save the city. Furious at being kept in the dark, Harlow understands her mission is far more dangerous than she realized.

Henry insists she ride on his horse for safety in the Drained Wood. As they pass through the city gates, Harlow is overcome with a deep sense of relief at finally experiencing freedom, which a confused Henry mistakes for sadness. Their journey is swift and tense until they are ambushed by a horde of Drained emerging from a thick, red blood mist.

During the Drained attack, Henry and Harlow are knocked from their horse, Nightsong. Henry finds Harlow fighting competently, and she reveals she can sense the Drained as an “absence of an aura,” even with her eyes closed. They fight together, using Henry’s sword, which is coated in well water that dissolves the monsters to ash.

Harlow is clawed in the shoulder and her wrist is broken, though she hides the severity of the injuries. To create a diversion for their escape, Henry cuts Harlow’s palm and uses her blood to lure away the frenzied Drained. Henry and Harlow flee on Nightsong and regroup with the rest of their party before arriving at Mountain Haven, a bustling and rebuilt fortress that surprises Harlow with its energy. Back at Havenwood House, Henry insists Harlow stay in his adjoining chambers. He takes her to a private washroom and uses his healing magic on her shoulder and wrist, discovering they were more severely injured than she let on.

The next day, Henry gives Harlow a tour of Havenwood House, which Harlow finds ruggedly beautiful with its wild plants breaking out of its ancient stone walls. Carrenwell House, on the other hand, is a little too tidy and pristine. Henry presents Harlow with a cloak embroidered with the sigil of Harvain, the Divine of Fortune, explaining the gift is a local custom and a sign of acceptance. They visit the armory, where Henry reveals that they coat their weapons in well water to effectively kill the Drained, a tactic Harlow realizes is unknown in Lunameade. He offers to trade the secret of their water source for her reasons for killing men, but she declines.

Henry then leads her to the ruins where his sister died during the attack 10 years ago. He warns her to stay out of the adjacent woods, which are the “hunt grounds” for the feast of Kennymyra, the Divine of Pleasure, the patron god of Henry’s people. During the hunt, dominants chase willing submissives through the forest. Inside an art gallery, a large white wolf named Kyrin appears. Henry explains that the wolf is not a pet but a companion. Henry forbids Harlow from leaving her room during the feast that night, as the hunt may be too much for her to process, but she secretly resolves to investigate. It is clear Henry’s people are closer to nature than the folk of Lunameade. Harlow also suspects that their society is more ritualistic and open about sex.

Before the hunt, Henry meets with his parents, who are concerned about their people’s growing impatience for revenge against the Carrenwells. Henry reports that Harlow is a capable fighter who can sense the Drained’s auras. After locking Harlow’s door from the outside, he tells Kyrin to watch her.

Henry joins Carter and Bryce at a tavern, where he discusses Harlow’s unexpectedly strong magic. Carter suggests she is deliberately letting information “slip” to manipulate him. At the hunt grounds, Henry prepares to participate, selecting a woman named Miriam as his prey. He notices his rival, Stefan Laurence, watching him with hostility. Henry suspects Stefan was behind an earlier attempt to test him by having a man named Seth attack Harlow. As the bell rings to signal the start, Henry heads into the woods.

In the hunt grounds, Henry quickly finds Miriam and begins kissing her, but he is distracted by thoughts of Harlow. He then senses Harlow nearby and dismisses Miriam. Harlow appears, cloaked but wearing a silk nightdress, and they exchange taunts. Annoyed by her defiance, Henry decides to show her the reality of the hunt.

He takes her to a ruined shrine where they watch Bryce engage in rough, consensual BDSM play with another woman. Henry holds Harlow, feeling her arousal as she watches, riveted. Bryce spots them and winks. Harlow abruptly pulls away and storms back toward the manor. In the courtyard, Henry confronts her for her recklessness, but she retorts that she will not be locked away. She slips inside before he can respond, leaving him to suspect she and her bodyguard, Gaven, are working together.

The next day, Harlow explores the library to learn about Mountain Haven’s marriage rituals. She picks the lock on a restricted section and discovers a book detailing the ceremony, which involves a public consummation before witnesses. Henry finds her and explains that the ritual is a test of their union’s legitimacy and his strength as an heir. If the couple can bring each other to orgasm, the sigil of Kennymyra above the bed will register their chemistry and bless the union.

Harlow and Henry argue about consent and control. To gain leverage in their tense negotiation, Harlow reveals a secret: She has never had an orgasm with a partner because her poisonous kiss is an uncontrollable reflex that kills, forcing her to be constantly on guard. Henry is surprised. He rightfully guesses that Harlow doesn’t just possess a poisonous kiss but can also summon poison to other parts of her body, which is why she could infuse venom in his wine. Harlow is taken aback by Henry’s ability to read her. She is tempted to think of him as her friend, but knows he is just a temporary presence in her life. The conversation between them turns sexual. Goaded by his challenge to “practice” for the ceremony, Harlow masturbates in front of him.

At a formal dinner with Mountain Haven’s leading families, Harlow endures their open hostility. Henry arrives late and forces her to give an impromptu speech. She addresses the crowd directly, acknowledging her family’s past failures and positioning the marriage as a way to secure the fort’s future. Her candor seems to soften some of the guests.

During the dinner, Harlow’s begins to suffer one of her chronic, debilitating pain episodes. Stefan Laurence, comes over to taunt Harlow; Harlow can sense his orange aura of manipulation, a gift from Polm, the Divine of Malice. As Henry coolly asks Stefan to leave Harlow alone, Harlow’s condition worsens rapidly. Her vision blurring, she signals her bodyguard, Gaven. Pretending to be drunk, she makes her excuses and leaves. Gaven helps her back to their rooms, where the pain becomes unbearable. Kyrin, the wolf, stays with her as she collapses on the washroom floor, and she asks a reluctant Gaven to remain with her.

Three days later, Harlow remains secluded in her room. Frustrated and jealous that his wolf Kyrin refuses to leave her side, Henry goes for a run with Bryce and Carter. Stefan confronts them and accuses Henry of betraying his people by killing Seth to protect Harlow. Henry calmly de-escalates the situation.

Bryce and Carter then reveal they have been following Henry out of concern for his safety. Bryce also reports that Harlow’s bodyguard has been requesting large quantities of ice. They conclude she must be ill and hiding it to avoid appearing weak. Carter suggests Henry use this opportunity to earn Harlow’s trust. Henry decides to show her the secret Mountain Haven Well. He finds Gaven guarding Harlow’s door and, after a tense standoff, Henry convinces Gaven to grant Henry entry by revealing the well’s existence and its potential to heal her.

Henry leads a blindfolded Harlow down to a secret, heated well carved from the mountain. Stunned by its existence, Harlow learns that its water is the true source that flows to the wells in Lunameade. When Henry presses her about her seclusion, Harlow lies, claiming the ice was for “pain tithes”—self-punishment to earn a favor from a divine—to control her magic.

As they bathe together in the well, Harlow is shocked to see Henry’s body is covered in vicious scars. Henry tells Harlow he will now share a few secrets with her so she knows he is trustworthy. The ring he wore the first time he met her was a creation of his sister Holly, blessed with protection magic from Varek, the Divine of Protection. The scars Henry bears are from his wounds during the attack by the Drained. He actually died during the attack, but was brought back to life by his mother, a resurrectionist. Harlow’s mouth goes dry with awe: Resurrection is the rarest of magical gifts. Henry tells her that the magic greatly drains his mother every time she uses it. Henry also shares that after his return to life, the Divine of Endings, Asher, granted him a gift: Henry can no longer be killed by any method that has already been used on him once.

Harlow is still processing the unbelievable fact of Henry’s resurrection as Henry recounts the traumatic fall of Mountain Haven. Overwhelmed by a horde of Drained, he and his sister Holly held the final line of defense. After Henry was mortally wounded, Holly sacrificed herself, unleashing her holy fire to incinerate the remaining Drained and burning herself to ashes in the process. His mother resurrected Henry moments after he died.

Henry then lists his subsequent deaths—by blade, poison, and drowning, among others—each making him immune to that method. Harlow realizes she can kiss him because he is already immune to poison. Overwhelmed by all the information, Harlow gets out of the water, accidentally revealing the severe, patterned burn scars on her lower back. Henry is shocked and demands to know who hurt her. She refuses to answer, stating he is entitled to her future, not her past. Instead, she reveals the truth about her seclusion: She suffers from chronic, crippling pain episodes, which no healer has been able to cure. Henry is filled with pity and promises she will always be allowed to rest when she is unwell.