The London underworld is in turmoil: the feared American gangster Clarence Devereux wants to expand his operations to England. Professor Moriarty is also said to have a hand in the game - but isn't he, like Sherlock Holmes, supposed to have plunged to his death at the Reichenbach Falls? And what role does the enigmatic detective Chase, who suddenly appears in London, play? As the power struggle among the crime giants claims its victims and a brutally mutilated body is discovered, Inspector Jones from Scotland Yard sets out to uncover the American's machinations. A bloody trail leads from the docks to the catacombs of the Smithfield Meat Market. Could it be that Moriarty is still alive? In the tradition of his Sherlock Holmes novel "The Mystery of the White Ribbon," Anthony Horowitz once again sends the detectives of Scotland Yard on a hunt for criminals.