At a dance given by Earl Dexter, his wife, for the gratification of a whim, wears a beautiful pearl necklace recently purchased by Viscount Acheson. Craig Dare, who is a gentleman thief, makes love to Earl Dexter's wife, and at the same time succeeds in stealing from her the pearl necklace and handing it out of the window of the house to Tony Oscaros, a chauffeur, who is none other than Dexter, who is leading a dual life.

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.

Bill Clayton is known as Broadway Bill because he is the most prominent Bill in the night life of the white way. Muriel loves Bill, but loathes his mode of life, and for her sake he goes to Underwood's lumber camp to work the alcohol out of his system. Hardigan. the foreman, thinks he is sent to spy upon his actions and makes several efforts to get rid of him, but in the end Bill thrashes the foreman, takes his place and wins the girl, though not before a curious chain of cross, purposes.