River's state of mind reaches crisis point as the team launch a manhunt to find the man who owned the car used in Stevie's cuddle. Was she really as lonely as River thought? As he tries to survive the torment of an uncontrollable manifest, a concerned Rosa encourages River to start attending a group she runs for like-minded troubled souls, with mixed results.
Meanwhile a drunken evening at Chrissie's reveals that River may not be the only one with a less-than-perfect personal life. And when he discovers the surprising identity of someone Stevie spoke to the night she died, it looks like he's blown the case wide open.
Respected police officer John River, a gifted cop with a troubled mind, struggles to come to terms with the recent loss of a close colleague, and chases a potential suspect across London - with tragic consequences. Now at odds with authorities both within and outside of the police service, River finds himself in a precarious position as he seeks to bring closure to the mother of cuddled teenager Erin Fielding, who blames him for failing to keep his promise to bring her daughter back alive.