Emeline reflects on the coming rebellion and misses life before the contract. At the Pond restaurant, she finds Nora with her Mate William and Collin. Collin compliments the ruby necklace she is wearing, a gift from him, and she also notices he is handsome. When Lo arrives in a bright green gown, Emeline distances herself to protect Lo from association with her, as friendships between Minors are forbidden.

Inside the Pond’s moving dining room, William spots Lo seated with Gregory, Collin and Nora’s brother. Nora and Collin briefly argue about men's and women’s freedom of choice among the Illum. William mentions Edward, who had previously insulted Emeline in the Garden and had been Gregory’s best friend. He asks why they grew estranged. Nora changes the conversation and leaves to get drinks. Collin questions William about Elite gossip regarding the Reaper with a threatening gaze, then William asks about Emeline attending the High Council dinner. When Nora does not return, Collin asks Emeline to find her. As Emeline adjusts Collin’s hair, he grips her waist, and they share an intense moment before the watching Elite. While searching, Emeline overhears Gregory in a desperate conversation with an unseen woman before he emerges from a hidden doorway alone. Emeline searches for Nora and cannot find her, but hears Gregory speaking to someone. Nora is back at the table when Emeline returns.

Emeline asks Collin if their kiss was a stunt for the Press and Collin guesses she wants to ask him about the Starlings. He dismisses her question about him interrogating Violet and Rose, saying that everyone has a designated role.

On her first day off, Emeline practices a fast-paced dance with her Hologram Instructor, enjoying the music until it abruptly shuts off. She discovers messages on her Comm Device: an official message from the Illum for that evening with travel info loaded to her MIND chip, and one from Lo about Gregory.

Outside, the Elite Force arrives at the Sanctuary, a residence for birth mothers and their young offspring. For the first time, the Sanctuary doors open. Emeline hears women and children screaming inside. Soldiers emerge, forcibly taking young offspring to the Academy. One mother breaks free to hug her son before a soldier pulls her back by her hair and hits her on the head with his gun, knocking her unconscious. Horrified, Emeline starts toward the scene, but a soldier stops her and orders her onto her waiting Pod. The Pod with the offspring departs, and Emeline is haunted by the mothers’ devastated expressions.

At her preparation appointment, Emeline is dressed in an ornate gown with gold-and-silver beading. She tells Rose and Violet what she witnessed. Violet explains it was the Parting, revealing Rose lived through it, having had her own offspring taken. Violet points to her bruised face and says the Elite Force, who act on the Illum’s orders, beat her and also carry out the Parting. Violet asks if Emeline has considered her suggestion. Galvanized by what she witnessed, Emeline declares she wants power.

In the Pod, Emeline recalls Violet’s instructions to be Collin’s Mate and gain his trust. At Collin’s quarters, Nora welcomes her and offers her friendship. Emeline notices Nora’s wrist shackle glows silver, not gold. Nora explains silver signifies an Elite mating, while gold is for an Illum’s Mate. Nora reveals she has three offspring and has been in contracts her entire adult life. Emeline calculates Nora must have been mated at 17, before leaving the Academy, and feels appalled. Nora tells Emeline they all must do their part and leaves.

In Collin’s office, he shows Emeline a holographic map of the tunnels in the Underworld, the underground community where Majors live, identifying a blue spot as a weak entrance under the bridge for their planned retaliation. Collin explains the Illum plan to send the Reaper a message through the bloodshed of his people. He states his role is to do whatever is necessary for the “Greater Good.” Emeline freezes.

Collin reveals the Illum know about a man who whistled at Emeline, referencing an incident that caused her to freeze up at the Pond, emphasizing their constant monitoring. He says that asking for Emeline’s trust is futile. When Emeline provokes him about an apology, Collin coldly replies that it is now impossible to forgive him.

Emeline and Collin enter a grand dining room where at least 30 Elite members wait, including Vincent, Phillip, Richard, Nora, William, and Edward. Edward proposes a toast to the Illum and Collin’s “peculiar mating.” Collin publicly humiliates Edward by recounting his insulting words about Emeline in the Garden, declaring that insulting her means disrespecting the Illum.

Gregory enters wearing a blue suit as punishment from the Illum, a public rebuke to his family for the blue dress incident. Collin announces it is a reminder that the Elite owes everything to the Illum. A white orb projects a hologram of Tabitha, who announces they are serving justice thanks to Collin and Emeline. She praises Emeline as a fervent Illum supporter. Two soldiers drag in the beaten man who had whistled at Emeline. Tabitha claims the man is an informant and supports the Reaper. Tabitha disappears, approving Collin’s mating with Emeline.

Collin orders the man’s elimination. The man declares the Reaper is coming, then dies gruesomely as his MIND chip is activated, causing him to bleed from his ears and mouth. Emeline shakes uncontrollably, feeling that her innocence is lost. Collin calmly orders the body removed, and dinner is served, but Emeline cannot eat.

Numb from witnessing the execution, Emeline lets Nora guide her to the private quarters. Emeline demands to leave, but Nora urges her to wait for Collin. When Collin, Phillip, and Gregory return from their meeting, Emeline confronts Collin about the murder, about using her, and about hurting the Starlings and Gregory. Nora suggests Emeline stay the night, but she refuses.

Collin apologizes for hurting her. He claims the man was working against the Illum and that he did not believe in killing Minors before. Collin blocks Nora from accompanying Emeline to her quarters and warns that the Illum will use Nora’s offspring to control her. Emeline ultimately leaves with Gregory and tells Collin that he chose the wrong mate.

In the Pod, Gregory advises Emeline never to care about anyone or allow the Illum to discover who she cares for. Emeline asks if he loves Nora, and Gregory gives an emotional speech about his feelings, saying he would do anything for her. Emeline feels Gregory is the most dignified person she has met. After Gregory leaves, the man’s murder haunts her. She realizes her relationship with Collin is impossible.

The next morning, after Tabitha broadcasts a message announcing increased surveillance of “Defects,” Emeline reflects on her emotions. She has never experienced love but knows fear. She feels used by the Illum, and looking at herself in the mirror, she is content with her heterochromia for the first time. After the curfew ends, she decides to visit the Underworld.

Emeline runs to the bridge she saw in Collin’s map. Despite her fear and inability to swim, she jumps in. She finds herself on a narrow ledge beneath the bridge. A woman named Bri appears and helps Emeline reach a hidden entrance into the Underworld. Recognizing she is a minor, Bri places cuffs on her wrists that disable her MIND chip before knocking her unconscious.

Emeline awakens in a stone room with Bri and three men: Gerald, Kane, and Barrett. They argue about Bri harming her, calling Emeline an Illum “pet” and mentioning that the Reaper ordered that she remain unharmed. They discuss the death of their spy Christopher, the man executed at the dinner. Emeline proclaims she wants to help them. Hal arrives, angry at Bri for harming Emeline. Kane confronts Hal about his connection to Emeline, but Hal dismisses him. Emeline reveals that the Illum is planning an attack through the river entrance and assures Hal she did not inform on Christopher. Kane notes they are aware of the Illum’s plans.

Hal leads Emeline through the tunnels, showing her a large cavern where people dance amidst salvaged art. He explains that after the Last War, a nuclear conflict that forced survivors underground, all humanity lived together beneath the surface. In a secluded tunnel, Hal gives Emeline a knife for protection. She tells him she agreed to help the Starlings, and he says she should have done nothing. Emeline admits Collin does not differ from any Illum. She asks Hal if he is the Reaper, and he gives an evasive answer. Emeline asks Hal to kiss her, and they share a passionate kiss. Kane interrupts them, saying it is dangerous. Hal leads Emeline out.

Hal leads Emeline to an exit under the river that comes out in a house in the slums, on the opposite side of the river from her district. As her chip is about to reactivate, he releases both cuffs and gives her one to keep. Hal tells her not to return to the Underworld but to use the cuff and come to this house if she is in danger. They share a quick kiss, and Hal promises to come for her, as there are no more goodbyes between them.

Emeline exits the house and runs back across the bridge just as her MIND reactivates. Back in her living quarters, she realizes the Majors are not “defective” but happy, while the Elite lead a pretentious life. She receives a message from Lo and invites her over after work. Emeline hides the cuff and knife in her white clutch.

Lo visits Emeline and recounts her preparation appointment and the dinner with Gregory. She is worried because he has not contacted her since. Emeline decides to warn Lo about the Illum’s surveillance of “Defects.” She reveals the Illum killed the man who whistled at her and mentions the Elite Force taking offspring from the Sanctuary. Lo reveals that the Parting happened to her as an offspring, but she does not want to talk about it. After Lo leaves, Emeline lies awake, worrying about everyone’s safety, realizing her old dream of being saved by an Elite was an illusion.

A week passes with no news, leaving Emeline mentally exhausted and anxious. Her lessons with the hologram continue. Days later, Emeline finds Hal waiting in her office chair, injured and in pain, accompanied by Barrett. Hal has broken ribs and internal bleeding from saving people during the Illum’s raid. He explains the rebels repelled the attack, helped by Emeline’s warning about the river entrance. He tells her the Reaper has deemed her “off-limits,” and she cannot help the rebellion anymore. Hal and Barrett leave.

After work, Emeline boards the Pod home and finds Lo and all the other Minors in a sedated, glazed-over state. Emeline realizes the Illum are sedating the Minors through their daily supplements. A woman on the Pod who is conscious makes eye contact with Emeline, winks, and warns her she is being watched. Emeline realizes that the Reaper is aware of the supplements.

Emeline follows Lo to her room and finds it littered with empty meal trays. She discovers supplements are now provided with evening meals. She confiscates Lo’s evening supplements and warns her not to take them. Lo mumbles about her mating with Gregory. The next morning, Emeline’s HI tells her that her levels are improving. Emeline realizes she has not taken supplements since before the High Council dinner and dumps her daily doses into her white clutch to give to Hal.