The discovery of a young boy's body sends Marcella and the team after a child killer.

Dr Fairclough tells Marcella that it might be a good idea to go back to the root cause of her blackouts - Juliet's cot death. But when she tries to relive that moment at her home, the resulting stress levels put her into another fugue state. Meanhile, the team is called out when the driver of a car abandons his vehicle after a fatal collision with a cyclist and police attending the scene open the boot to discover a body surrounded by the same stuffed toys found with Leo.

Marcella digs deep in her attempts to take down Phil Dawkins, but her dogged pursuit has tragic consequences, causing her to question everything. Meanwhile, her ongoing blackouts mean she has to face up to the threat of losing her children.

Adam gets away from the killer's prison but loses consciousness while trying to escape in the car of an elderly couple. Meanwhile, Marcella confronts Reg about a binder that was stolen from his house, while Phil sets his sights on the detective.

Kevin Hoffs and his blue lorry are found abandoned in a lay by. Leann informs Marcella that the lorry had been there for 36 hours. After analysing Adam's phone records, the team become aware that Adam had contacted the KidsCall helpline. Marcella heads there to retrieve the records and Maya is helpful despite both women having Tim Williamson in common. From Adam's records they see that he'd admitted to being abused by his father but his father has alibis for many incidents surrounding the case.

The arrest of Vince Whitman causes massive fallout between Tim and Marcella. Meanwhile, Postfeed24’s internet viral video leads the team to discover another body much closer to home.

Marcella heads to Nigel Stafford's house to question him. As she walks around the house she finds a small grave before heading inside the unlocked door. Inside she's confronted by Nigel, holding a knife.

Marcella has no time to lose as the killer has Edward. Following leads she races to the killer's house, but finds it empty except for a ringing phone. However, a premonition offers up clues, but can she get to her child before it is too late?