Plot synopsis: The deceased owner of a medieval castle stipulated the following in his will: The heir to his mighty estate would be the elder of the two stepsisters, Katharina and Margrit von Kronberg, namely Margrit, if she married Heinz Wagner, a cousin who had just returned from captivity. When Margrit observed Katharina and Heinz rendezvousing at a nearby lake, Margrit demanded that her husband leave the castle immediately, before she, the elder sister, and Heinz were married. Furious, Katharina then plotted to poison Margrit. Only when Katharina dreamed that the village youth would avenge Margrit's violent death according to ancient tradition and that she, Katharina, would be burned on a pyre like witches in the Middle Ages, did she, after awakening from this nightmare, abandon her bloody plan. Her change of will is rewarded: Heinz has decided to marry Katharina and not Margrit.