Mr. Sweet turns to his colleague Tarot, a mystery-solving stage magician, who, with the aid of his stage-manager, Sam Maxted, immediately sets off to track down the thieves. While following a villain named Teddy Talk, Tarot and Sam, together with Lulli Palmer, Tarot’s assistant, discover that the brains behind the theft is Madame Midnight, head of a Mafia-like organisation run from a monastery.