Faye pulls alongside Corrine’s boat. Corrine claims she ran out of gas. Faye quickly formulates a plan: she will tell Corrine that she is on her way to the mainland to call the police and urge her to come along (rather than going to the island), but she will not reveal any of the secrets yet. Faye plans to tell the police that she killed Campbell in self-defense and then bribe Emma to corroborate her story. However, as they talk, Faye gradually deduces that Corrine may be fabricating the story about having run out of gas, and may have been waiting for her. 

By the time Faye realizes that she should not trust Corrine, the latter is threatening her with a gun. Corinne makes comments revealing that she has been in contact with Henry (she knows, for example, about Henry and Faye going to the mainland together). After Faye admits that she trapped Henry in the cabin, Corrine orders Faye to climb into the boat with her. They return to the island together.

Corrine holds Faye at gunpoint, forcing her to free Henry. Corrine and Henry force Faye into the boat, and they head toward PT’s cabin. Faye can tell that Corrine and Henry are working together, but she is unsure whether Corrine knows about Campbell’s death. When they retrieve shovels from the shed, Faye panics, fearing they are going to kill her. She blurts out that Campbell is dead, hoping this news will shock Corrine. Corrine briefly feigns horror and surprise but then reveals that she already knows that Campbell is dead. She knows that Emma and Campbell were having an affair, and is planning to pin his death on Emma. 

Faye is unsure of the full extent of what Henry and Corrine have been colluding on, but she realizes that the plan has been perfectly executed to make Emma appear guilty: She has Campbell’s car. Despite Corrine ordering her to move into the woods, Faye faints.

Faye awakens inside PT’s cabin, where she is held captive by Henry and Corrine. When she questions why Corrine is not more upset about Campbell’s death, Corinne reveals that she and Henry “were planning on offing him anyway” (240). While Corinne isn’t bothered by Campbell’s death, she is angry with how Henry and Faye’s dalliance has disrupted carefully crafted plans. Corinne explains that when Henry and Faye were grocery shopping on the mainland (after dropping off Emma), they were seen together by the island caretaker. The caretaker reported this to Corinne and she had to bribe him into silence. 

The discussion of bribing the caretaker leads Faye to realize that Henry and Corinne have some sort of financial motivation for their plan. Still trying to gain the upper hand, she tells Corinne that Campbell and Henry killed Sarah and passed her death off as suicide. Corinne reveals that she was the one who masterminded this plan: When Henry and Campbell called her immediately after the accident, begging for help, she assisted them with covering up the incident and was the one to realize that Sarah’s struggles with infertility could be used as evidence of suicide. 

Corrine then reveals her own painful history of infertility. She struggled to conceive and used an egg donor to conceive her son. She conceived naturally six months ago and was elated by the prospect of a second child; however, she suffered a late-term miscarriage after catching Campbell with Emma. Faye becomes more frightened as she realizes the depths of the anger and pain that is motivating Corrine.

Henry, Corrine and Faye walk into the woods. Faye is cold and Henry hands her a sweater from PT’s cabin; she finds a receipt in one of the pockets. As she walks, Faye recalls a confrontation with her husband during a recent vacation. She had hoped the trip would help them to reinvigorate their sex life, but her husband continued to lack interest. When she confronted him, he revealed that he found her more sexually attractive earlier in their relationship, when “you looked up to me […] I miss when you needed me a little bit more” (253). 

Eventually, they come to the spot where Sarah was buried, and where her skeleton is now partially exposed (after PT dug it up prior to his death). Henry and Corinne dig up the remaining bones and pack them up in a bag (to ensure no one else finds the body). However, as they walk back towards the cabin, they encounter a pair of hikers who have gotten lost. Acting calm, Henry gives them directions. He refers to the property as belonging to him.

After returning to the cabin, Faye asks Henry why he said that PT’s property is his. Corinne reveals that PT’s property was left jointly to Campbell and Henry. The property is extremely valuable and could be sold for a lot of money. Campbell was resistant to selling, but now that he is dead, Henry and Corinne can sell it and split the profit. (This explains why they were planning to kill Campbell and not upset that Faye did so first.) 

Corinne details the next steps in their elaborate plan. She will call police, claiming to have found Campbell’s body (which is still at the main clubhouse, where Faye killed him). She will explain her presence on the island by telling officials that she became worried after Campbell stopped responding to calls and messages, and that she went to the island to check on him. The police will be able to tell that Campbell was violently killed and will begin seeking out a suspect. Meanwhile, back at the college, Corinne’s brother Win is going to give Emma some contaminated drugs and ensure that she dies from consuming them. Corinne has prepared a fake suicide note, in which Emma confesses to having killed Campbell. The note, paired with video footage from the train station of Emma driving away in Campbell’s car, will ensure it looks like she killed him. Emma’s death will ensure she can’t contradict the story about Campbell’s death, nor can she ever reveal the truth about Sarah’s death. 

However, Corinne expresses worry about Faye’s ability to disrupt their plan. While it would be risky for Faye to reveal that she killed Campbell, she could plausibly pass the crime off as self-defense; Corinne notes that “in this day and age, women can pretty much make a case of anything” (262). To ensure Faye never comes forward with the truth, Corinne wants evidence that Faye willingly came to the island to pursue an affair with Henry.

Corrine dumps Sarah’s bones into the lake. She forces Faye back into the small cabin with Henry, locking them inside. Corinne demands that they film a sex tape: this tape will make it impossible for Faye to claim she was brought to the island unwillingly. If she tries to come forward, “it will look like I killed Campbell because he discovered I was having an affair” (265). Confused and angry with Henry’s many lies, Faye asks why he concealed that he was colluding with Corinne, and why he wants to sell the property. Henry explains that is financially ruined. His wife has a suspected bipolar disorder that manifests in manic spending sprees, which have led to massive debt. She has committed fraud and made financial choices that have led to them being evicted from their home. 

Henry claims that he has reassessed their shared history and emotional dynamic. He says that Faye cannot tolerate love and vulnerability; he never wanted to be domineering and controlling but he knew that if he didn’t maintain this façade, she wouldn’t love him. Faye tells him she was sexually abused as a child, and that this experience fundamentally shaped her understanding of her worthiness. They have an intense but ambiguous sexual encounter that Faye describes as something she is forced into yet also wants; they film the encounter on Henry’s phone.

Faye falls asleep and is woken by Henry, who tells her the police are outside the cabin. Panicked by the prospect of losing him, Faye calls out to the police, claiming they are being held hostage by Corinne. When the police confirm that they have arrested Corinne, Faye fabricates a cover story. She claims that “[Corinne] killed her husband. And then she locked us in here, and we have been so scared she was coming back to kill us” (277). 

The police confirm that they came to inspect the property after two hikers (the individuals who were lost near PT’s property) came across a note written on the back of the receipt and dropped on the trail. The note said “help” and aroused concern. Faye wrote this note after finding the receipt in PT’s sweater pocket, while she was being forced to walk with Henry and Corinne. At the time she hoped the note would alert someone to free her from them, but now she claims that she and Henry are both victims of Corinne. The police seem sympathetic to this story and promise to liberate them from the cabin.

Faye and Henry are taken to the local police station to be questioned. Faye is told she is not under arrest. She tells a lengthy story about the events on the island, though the details of what she says are not included in the text. She also calls her husband and tells him “an abbreviated version of the story I’ve been telling all day” (282). He hangs up angrily.

At dawn, Faye is released from police custody. However, she is told she can’t return to California yet, as she may be needed for further questioning. Faye recalls the story that she and Henry quickly came up with together, to ensure their stories would match when they were questioned. They claimed they were having an affair and had gone to the island to be alone together in secret. They heard strange sounds from the clubhouse and found Corinne with Campbell’s body. Corinne took them across the island, intending to kill them and hide their bodies. During this time, Faye was able to drop the note (explaining why it was on the trail leading to PT’s property). Corinne panicked and returned them to Henry’s property, where she locked them in the cabin. This story explains all of the strange events, while making Corinne appear guilty and protecting both Faye and Henry. 

Outside the police station, Faye runs into Henry’s arms and professes her love. Then her narration breaks off, revealing that everything up until this point has been a movie pitch delivered to a group of Hollywood executives.