In the shadowy hallway of the clockmaker's old couse a policeman is found murdered, a steel clock hand embedded in his neck. A thing with gilt-painted hands scuttles across London roof-tops. These are just two of the frightening scenes in Dr. Gideon Fell's most frightening case- a case that starts with a knife-weilding shoplifter and ends with a portly detective using a mad-man to capture a murderer.