When a young woman is found brutally murdered on a train, the police call in a brilliant but unstable psychologist.

Kelly is put into Fitz's care after a lack of evidence. But after another murdered woman is found, Kelly is arrested and DCI Bilborough orders Fitz off the case. Fitz and DS Penhaligan collude to find out the truth.

Fitz continues his volatile liaison with the Manchester police force when a latter-day Bonnie and Clyde hit town leaving havoc in their wake.

The search for Sean and Tina is intensified when someone close to Fitz and his police team is murdered.

Fitz has Tina in custody, but is racing against time to get her to reveal Sean's whereabouts before he kills again.

Maverick psychologist Fitz is called in to help the Manchester police track down a missing boy.