The sister of a famous, but as yet uncaught, criminal named "The Hexer" is murdered. Inspector Higgins of Scotland Yard believes that "The Hexer" will surface to take his revenge on his sister's killers, and plans to set a trap to finally capture him. However, soon bodies start piling up, and it looks as if "The Hexer" may get away yet again.

A ring of counterfeiters is flooding the country with phony money, and suspicion falls upon a wealthy playboy who may--or may not--have amnesia.

A hooded serial killer finds a novel way to murder his victims--he lashes them to death with a whip. The police try to track him down before any more murders occur.

Both Scotland Yard and an amateur American sleuth are tracking a master criminal known as The Frog. This moniker refers to the bulging-eyed mask worn by the evildoer, and is reflected by the frog icons painfully tatooed onto the forearms of his henchmen. The trail leads to the country manor of an enigmatic, steely-eyed nabob, whose repressed son has eyes for the artistes at the Lolita cabaret, and whose lovely daughter captures the fancy of both the American playboy and the villain himself. Murder, kidnapping and seduction ensue.

After the mysterious crash of a millionaire's private plane, scientists secretly harvest the dying man's brain and keep it alive in a laboratory in order to communicate via telepathy.

Dr. Mabuse and his accomplices steal all kinds of attributes from a National Research Institute (including female staff members) in order to complete his own evil mind-control ray. Dr. Mabuse has this impressive and horribly scarred man-monster that kills for him while the entire police force desperately tries to catch him.

Strange things happen in a revue theatre. The dancer Maria seems to be hunted by an invisible admirer. When the body of a probable FBI agent is found in a trunk the police asks FBI man Joe Como for help. Como gets interested in the revue theatre and an ominous transport firm soon. When he is receiving mysterious threatening letters he is sure that Dr. Mabuse has risen again. But what is going on at "Enterprise X" so that both the goverment and the mad genius in crime are interested in it?