To stave off bankruptcy, the Marquis of Tergall is forced to sell his wife's jewelery, but both the jewels and the money from the sale are stolen by two members of Fantômas' band of crooks. Meanwhile, Fantômas is in prison in Belgium. In a desperate bid to bring the master criminal to justice in France, Inspecteur Juve contrives to allow Fantômas to escape, but the plan goes awry. Juve ends up taking Fantômas' place in prison and Fantômas escapes to freedom, later assuming the identity of an investigating judge. Fantômas wastes no time using his new identity to his evil advantage.