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.
Arthur Milton aka Der Hexer (The Magician/Ringer) must return to London after his calling card was left at the scene of a murder he did not commit.
