One cold spring morning in County Cork, two fishermen find a bundle of rags floating in the Blackwater River: the mutilated corpse of a retired music teacher. His hands and feet are bound, and his neck bears the mark of garrotting wire. The Garda want to wrap this case up before the press get hold of it. But when a second man is found murdered, the body bears all the same marks as the first. And Detective Superintendent Katie Maguire fears this case carries the hallmark of a serial murderer ...