River

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.

Following the murder in the public library, River and Ira must track down the killer. Their journey takes them deep into the world of the undocumented migrant community in London, a world of international hostels and immigration lawyers. They begin to get a sense of what it was that Stevie might have been unravelling before she died. Was it these investigations she was punished for?
And as River finds himself back at the hearing voices group, an unfortunate contribution leads to River being drawn closer to Rosa, his colleague and counsellor. But as River finally finds some solace, Ira is led into the heart of the storm, and the spotlight is thrown onto somebody with an awful lot to lose.

River is convinced that Stevie's investigation into the exploitation of undocumented migrants holds the key to her murder. Further questioning of someone close to the team reveals a system of immigration cases that could lead into some very unexpected places. When a common link to certain businesses is found, it all starts to fall into place for River, with unfortunate repercussions.
As Stevie's loved ones reel from the truths unearthed, River holds the future in his hands. How will he keep his final promises to Stevie? How can he keep her secrets for her and do what is right? And, if he solves her murder, can he cope with losing her forever?