Stella Donovan is a reporter, sent out by her newspaper to cover a society circus being given by millionaire Frederick Cavendish. The circus is exclusive and reporters are not allowed, but Stella cleverly contrives to assume the role of one of the lady performers; she even carries out the wire-walking act of the performer she is impersonating. While engaged In filling this role Stella overhears a plot against Frederick Cavendish, who has just made a will disinheriting his nephew, John Cavendish. John and tricky lawyer Enright are in on the plot, assisted by actress Celeste La Rue. Their plan is to do away with Cavendish and destroy the will so that John can inherit the property. Jim Westcott, a young mining man from Arizona, comes to see Frederick Cavendish on business. They quarrel, and later Westcott is falsely suspected of killing Frederick Cavendish. The latter disappears during a fire in his home and is thought to be dead. Stella and Westcott unite forces to try to recover the will. They meet with many perils at the hand of Enright and his followers, and are assisted at crucial moments by a strange being known as the Lion Man.