Detectives Sarah Collins and Steve Bradshaw investigate the deaths of the long-serving police officer Hadley Matthews and the 15-year-old Libyan refugee Farah Mehenni, who both fell from the roof of Portland Tower in south-east London.

Sarah convence finalmente o chefe, Tim Bailie, a tornar público o desaparecimento de Lizzie.

Lizzie decides to turn herself in, but first she meets Kieran Shaw in secret, who tries to persuade her not to implicate herself; when Sarah finally interviews Lizzie, the explosive truth about the fatal night on the roof of the tower emerges.

Sarah investigates a cold case; Lizzie responds to a domestic violence call.

Sarah and Lizzie find themselves working on the same murder case.

As the manhunt closes in on Brannon, Sarah realizes where Tania's body might be buried.