The Duchess of Cambyses commits all sorts of abuse on her subjects. A mysterious mute pilgrim, Damy, knows that the real Duke of Cambyses is young François, whose father has been murdered and whose mother Cristine has been locked up in a tower. A friar, Lebois, confirms, with a written testimony, the truth of this assertion. When the Duchess discovers she is only the daughter of a servant, she unleashes her ferocity and eliminates all the people who could testify to the King of France, Louis XV, to have her deposed. But a court jester, Polly, helps François, and his companions, when the marquise kidnaps Elisabeth, François's fiance. After many ups and downs, all the evildoers will get what is coming to them.