A corpse is discovered in the middle of the city of York. It is of a male; with no identification, shot, and tortured before his murder. It seems to be a professional hit, by the look of it. Gary "Hammer" Sledge turns out to be part of a large family well-known to the police, and most with previous form, and out for revenge at the killing of one of their own. Gradually people talk; hints are dropped; and trails appear - all leading to a man with no record and who has never been inside a police station. But the police know him - he's connected to another unexplained sudden death, and another, and a few more. Detective Chief Inspector George Hennessey and his stalwart assistant Sergeant Yellich need to find this Mr Big - who has a particularly chilling method of disposing of the human evidence...