River

Struggling to come to terms with the loss of a colleague, John River chases a potential suspect across London; meanwhile, the mother of a murdered teenager grows desperate and blames River for failing to make good on his promise to find her daughter.

Still wracked with grief at the death of his colleague, River's mental fragility is further strained as he begins to suspect that the man he chased to his death was innocent.

With his career and access to the Stevie case resting on the outcome of his psychiatric report, River must keep his unofficial investigations into Stevie's death to himself, creating tension with his new partner Ira.

The investigation into Stevie's murder changes direction when CCTV footage shows her to be closely involved with an illegal immigrant who owned the car that was used in her murder; the police launch a manhunt to track him down.

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.

River is convinced that Stevie’s investigation into the exploitation of illegal immigrants 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.