Pip goes to the Bell house at night and tells Becca she came to check on her after the discovery at Elliot Ward’s house. Becca invites Pip inside and makes tea. Becca explains that the girl Elliot kept was identified as Isla Jordan, a vulnerable missing woman who has come to believe she is Andie Bell after years of captivity.

Pip then confronts Becca with the truth: Becca knew the captive girl could not be Andie because Becca had killed her sister. Pip reconstructs Becca’s assault at a calamity party, explaining that Max Hastings drugged and raped Becca with Rohypnol. Becca confirms that she searched Andie’s room, found Andie’s burner phone and drugs, and discovered Max had bought Rohypnol from Andie.

Becca describes waiting for Andie to come home, hoping her sister would comfort her and help punish Max. Instead, Andie dismissed Becca’s pain, warned Becca not to expose her, and cruelly insulted her. During the resulting struggle, Andie fell, lost consciousness, vomited, and choked; Becca froze in anger and panic, then realized too late that Andie was dead. Becca hid Andie’s body in the septic tank at the old farmhouse on Sycamore Road, dumped Andie’s car on Romer Close to implicate the dealer, and later sent Pip threats when Pip’s investigation endangered Becca’s secret.

Pip tells Becca she forgives her for Barney’s death and came to warn her to flee before the police make the connection. As Pip speaks, the drug Becca put in the tea takes effect. Becca admits she kept some of Max’s Rohypnol pills and says Pip’s knowledge makes Pip a danger. Pip tries to vomit up the drug, fights Becca off with a stool, and escapes into the woods while hallucinating through the fireworks.

Becca catches Pip and tries to strangle her, but Becca finally stops, saying she cannot do it. Ravi and Pip’s dad arrive moments later after Ravi tracks Pip’s phone location. Pip, drugged and disoriented, tells Ravi that Andie is in the septic tank at the Sycamore farmhouse and that Becca put Rohypnol in her tea. Ravi comforts Pip while Pip’s dad restrains Becca, and police and ambulance lights arrive through the trees.