Episode 4

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 murder. 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.