In this entry in the Lone Wolf series, the first to have a soundtrack, the jealousies of the King and the coquettish Queen are chronicled. When His Majesty learns that his wife has given the ring he gave to her to her lover, the King plans a large ball and demands the she wear the token. As her lover is a military attache, he is not in the palace, and the queen must send her lady-in-waiting to bring it back. En route, the lady meets a thief and they team up. She does not know that he has been dispatched by the King to steal ring from the attache.

When Marcel, a waif, saves master crook Burke from the police, Burke adopts the youngster and teaches him his profession. Years later, Marcel has become a master crook himself, working under the name of Michael Lanyard. His clever work baffles the Paris police, who dub him "The Lone Wolf". The Pack, a gang of criminals, notifies The Wolf that unless he joins them, he is marked for destruction. Lucy, an undercover agent masquerading as a crook to expose the gang, helps The Wolf escape. This inaugurates a series of adventures in which Lucy and The Wolf are pursued by the gang, finally making their escape to England by plane. The Pack follows, only to meet their death in a plane crash. Liberated from his tormentors, The Wolf vows to go straight and marries Lucy.