The Marquis De Sade has been arrested for his writings of pornographic nature by order of Napoleon. Declared insane, the Marquis is forced to spend the rest of his days at the asylum at Charenton....

The Marquis De Sade has been arrested for his writings of pornographic nature by order of Napoleon. Declared insane, the Marquis is forced to spend the rest of his days at the asylum at Charenton. There, he forms bonds with the other inhabitants and learns how to manipulate them to his will. He also gets the adoration of a fan who works as a laundry lady at Charenton, Madeleine, who secretly sneaks out the Marquis' new writings to sell for him. The head of the asylum, the Abbe du Coulmier, also has a soft spot of Madeleine and tries to keep her away from the Marquis' dark writings and bad influence. When Dr. Royer-Collard is called in to try to help tame the Marquis, things start to go amiss. The Marquis' exploits and publicizes Collard's new marriage to a young girl, Simone, who was raised in a convent. Simone finds this quite amusing and sneaks past her husband to become engrossed in the Marquis' writings, and lifestyle. The inhabitants of Charenton are all growing mad thanks to the Marquis' influence, and one night when all hell breaks loose, there are consequences when a life is lost in the madness.