Inspector Juve is scorned for his belief that a criminal, Fantômas, is the offender in a series of murders and thefts. Juve accompanies a friend with a winning lottery ticket on the train to Paris. The woman is killed and the ticket stolen. Juve is convinced that Fantômas is Mr. Gurn.

With Inspector Juve missing, Fandor takes over the investigation. Fantômas poisons the newly bankrupt Baroness de Vibray and Jacques Dollon is questioned by the police and arrested. When Fandor arrives at the prison to interview Dollon it is reported that he hanged himself in his cell. However, the body has disappeared!

With Fandor mistaken for a king and framed for murder by Fantômas, Inspector Juve sets out to prove his innocence.