What drives serial killers to kill? Well, according to statistics, their main motive in the vast majority of cases is sexual. Serial killers often believe they're much cleverer than the police and will never be caught. They sometimes single out police detectives and taunt them with confident clues, always staying one step ahead. And they often have obsessions with common themes: time-keeping, tidiness, religion, dates.... OK, those are the stats, but what drives Kieran and Chris to kill? He's an ultra respectable deputy headmaster at an equally respectable public school in wealthy Cheshire, where everything runs like clockwork. Chris, meanwhile, is a carer forterminally ill patients at a hospice. But Kieran's blood runs cold. He is pure, conscience-free evil. Since the loss of his wife to AIDS, he wants someone to pay, and someone will. Chris's blood runs hot, needing ever-higher highs to get her past the pain of each working day. From the caterpillar of Chris emerges the black butterfly Ruth, seeking the forbidden: sex, booze and - ultimately - death. Her assumed name, as used in the Internet chat site where the two first meet, is not chosen by accident: she would have been Ruth Ellis if the real Ruth Ellis hadn't beaten her to it. Kieran, following her lead, takes on the cyber-persona Frank, modelled at a whim on 'Mad' Frankie Frazer, henchman to the Kray twins. That's what drives these serial killers. First, he kills a prostitute; purely so that he can observe her path into the next world. Then they both happen across a woman injured in a car accident; she is sent in the same direction. In total disrespect for the abilities of the Cheshire police, they invent a trail of false clues, false DNA and an intriguing pattern to the mounting deaths. The police have one weapon these killers can't anticipate, though. Tom Hamilton is an ordinary copper; nothing special. His results are about the same as any other police detective. Until one day he is overtaken by a vision of a crime, so vivid that he's able to solve it and get a conviction. The gift stays with him, but he can't control it: the visions appear when they want to, definitely not when he wants them, and they only show him the crimes through the criminals' eyes, never quite what he needs to see. The police authorities have tried tests, psychiatrists, hypnotists... Nothing can stop or control Tom's visions, until the gift everyone says he has turns into his own personal curse. They don't know whether to pension him off or give him a medal. Only one officer seriously believes in Tom - his boss DCI Moore. In an effort to increase the effectiveness of Tom's gift, they team him up with criminal profiler Maddy, bypassed for promotion so many times that this is probably her last chance. She failed her recent exams and her personal life is a mess, but she's ready to take on the enigmatic Tom and his protective boss Moore. So follows a game of cat and mouse, with each victory reinforcing Kieran's belief that he is better than his pursuers will ever be. It needs luck, and it needs vision. And Tom has both. Contains some adult scenes of a sexual nature.