DI Martha Bellamy welcomes back DS Jack Weston after a period of enforced leave following the paedophile investigation, warning him this is his final chance. Jack and DC Charlie Steele investigate when a popular art teacher is found with life-threatening head injuries at a sixth-form college, with suspicions falling on handyman Ben Peel and head Rory O'Hanlon.

The detectives investigate when a young woman is fished out of the Thames in the middle of the night, badly burnt and barely alive, with the only witnesses at the scene being a few homeless people who saw a man with a white van dumping the body in the river. Charlie runs the victim's distinctive necklace through the database and links it to Sian Jenkins, who was registered as missing in 2012, and events take a further turn when DNA taken from under her fingernails is matched to a girl who disappeared when she was eight almost a decade previously.

When 19-year-old Asif Khan is left fighting for his life after a petrol bomb is thrown through the window of his family home, his father Jamal is quick to point the finger at Gregor Forrester, who owns the plot of land next to the Khans. Jamal has been on the receiving end of threats and intimidation ever since he turned down Forrester... s insultingly low offer to buy his house.
Forrester and his nasty tactics are well known to Martha and Jack, but they have never managed to make any prosecution against him stick. Jack, in particular, has a grudge against the property developer, as his right-hand man is disgraced ex-cop David Eboda, Jack... s former mentor in the force. Martha orders Jack to go by the book - she has no intention of losing Forrester by any rash act of his, and when Charlie learns why Jack is so keen to get a result, she also warns him to be careful. As a result the case is making no headway until Jack uncovers some CCTV that blows both Forrester and Eboda... s alibi out of the water, and Charlie receives some forensic evidence that adds a whole new dimension to the case.

The team are called into investigate after a teenage girl is discovered naked on some waste ground suffering with some life-threatening injuries.