Pip parks outside 42 Mill End Road and calls 999, telling the police that Elliot Ward kidnapped Andie Bell, murdered Sal Singh, and may still be holding Andie inside. Despite the operator ordering Pip to stay outside, Pip hangs up and approaches the house, where Elliot answers in fear.

Pip tells Elliot that the police are minutes away and demands the truth so she can help Cara, Naomi, and the Singhs. Elliot lets Pip in, and in the kitchen, with the front door left open for the police, Elliot admits that the girl is alive and in the house. Elliot explains that Andie began pursuing him after Isobel's death, that Elliot secretly texted Andie, and that Elliot slept with Andie twice at the Ivy House Hotel. Pip condemns Elliot for exploiting a vulnerable seventeen-year-old student.

Elliot says Andie then threatened to expose him, but Elliot found a way to hold Andie off by using knowledge of Andie's cyber-bullying. On 20 April, Andie came to Elliot's home angry because Elliot would not help Andie get into Oxford as Elliot had helped Sal. During the confrontation, Andie destroyed Isobel's paintings, Elliot pushed Andie, and Andie hit her head on Elliot's desk. Elliot says Andie left while injured, leaving her phone behind, and Elliot panicked when Andie was reported missing.

Believing Andie might be dead and fearing Naomi and Cara would lose their only remaining parent, Elliot framed Sal. Elliot used knowledge from Naomi's therapy diaries to make Naomi and her friends withdraw Sal's alibi, lured Sal from school to Sal's house, drugged Sal, took Sal into the woods, forced Sal to swallow more pills at knifepoint, suffocated Sal with a plastic bag, sent the confession text from Sal's phone, planted Andie's dried blood under Sal's nails, and left Andie's phone in Sal's pocket.

Elliot says he later realized Andie had not died from the head injury when Andie's car and blood were found elsewhere. At the end of July, Elliot saw Andie walking from Wycombe toward Kilton, dishevelled and apparently affected by drugs. Elliot says he took Andie to the empty Wendover house because Andie's return would expose that Sal had been murdered, then locked her in the insulated loft, where Elliot has been bringing food, cooking, letting her shower, and watching TV with her.

As the police arrive, Pip tells Elliot not to reveal the hit-and-run or the destroyed alibi, because Pip wants to protect Naomi and Cara. Pip tells Elliot he will never be forgiven for killing Sal, destroying Sal's family, threatening Pip's family, and, as Pip believes, killing Barney; Elliot denies knowing about Barney. Elliot surrenders to the police for Andie's abduction and Sal's murder. While officers are distracted, Pip grabs the loft key, opens the hatch, and climbs up to find a young woman in the loft. The young woman introduces herself as Andie, but Pip realizes that she is not Andie.