As a series of rolling blackouts plunge the city into darkness, Detective Aidan Waits sits on an abandoned hospital ward, watching a mass murderer slowly die. Transferred from his usual night shift duties and onto protective custody, he has only one job – to extract the location of Martin Wick’s final victim before he passes away. Wick has spent a decade in prison, having confessed to an unspeakable crime that shocked the world and made him into a national hate figure. But when an audacious assault leaves one police officer dead and another fighting for his life, Wick’s whispered final words will send Aidan on a journey into the heart of darkness. Manipulated by a psychopath, and haunted by terrifying hallucinations, Waits can’t even protect those closest to him. Out of friends and out of time, he realises that an unfeeling, unfailing contract killer is at work. And Aidan’s name is next on the list.