People are predictable. That’s what makes them easy to kill. Detective Chief Inspector Prosper Snow is in charge of an investigation into a serial killer called The Oracle who turns his victims into macabre works of art. But Prosper harbours a dark secret of his own. He and his old school friends were members of a group called The Kult who made a pact to dish out their own form of vengeance on bullies. Now a member of the group puts their friendship to the test when he makes a far darker request: that they murder someone that raped his wife. To get away with murder, the friends decide to blame it on The Oracle, but events take a chilling turn when the instigator turns up dead, his body fashioned into a disturbing work of art. Now, one by one, the members of The Kult are being hunted down. Just when Prosper thinks things can’t get any worse, his wife is kidnapped and he knows that if he goes to his colleagues for help, he risks his dark deeds being unearthed. If he doesn't, he risks losing all that he holds dear.

Murder makes monsters of people. Prosper Snow knows that better than most. Now he’s back on the trail of another serial killer, only this time there’s far more to the case than meets the eye. Thwarted at every turn, Prosper unwittingly uncovers a human experiment more monstrous than anything he could ever imagine. Now the only way to crack the case is to work from the inside and join a shadowy government agency that operates outside the law. Only he might be too late as the experiment has spiralled out of control.