DI Will Wagstaffe is at London City Airport when his travel plans are put on hold. His colleague, DC Josie Chancellor calls to inform him of a gruesome murder. Staffe, along with Josie, DS Dave Pulford and DS Rick Johnson, are confronted by a horrific scene. A man in his early-forties, has been brutally murdered. As the team investigate further, they learn that the victim was arrested two and a half years ago on suspicion of sexually assaulting his young step daughters, Holly and Jasmine. He was remanded in custody for three weeks but there wasn't sufficient evidence and Collins was released. As the story unfolds, Staffe and his team delve deeper into the morally complex crime.