After a police operation ends in catastrophe, DCI Eve West is suspended. She faces expulsion from the force, until John Duran - a violent criminal Eve incarcerated, still serving his sentence - offers to help clear her name. But nothing comes without a price.

Duran wants Eve to help free a fellow prisoner, who he claims has been wrongly convicted of murder. But as her investigation takes a dark turn, Eve finds that more than just her job is at stake, and realises Duran is a dangerous man to trust...