Series 4

A young Estonian woman is found dead on a piece of waste-ground, suspected of being buried alive. As the team piece together her movements, they uncover a world of prostitution and drugs hidden behind a respectable veneer.

The team are dismayed to discover that an arson attack at the Osgood's house has injured Michael and killed his autistic son Robbie.

A husband and daughter struggle to come to terms with their grief when the body of wife and mother Anaan Kamel is found washed up by an underground river.

Geoff has become a marked man and Banks decides to put both him and his daughter Evie under watch at an anonymous hotel whilst he increases the search for Mullen.

When the body of an undergraduate is found dumped in a ravine, the investigation into his stabbing reveals he was far from being a model student.

Helen works hard to win back Alan's approval as they try to find the killer and prevent Josh's father from seeking a revenge of his own.