Lilian Harvey plays a young heiress in long-ago France named Madelon who is raised by her grandfather as a boy in order to frighten away fortune hunters. But when the old man dies, her guardian Cesaire wants to marry her off to the rich prefect Barberousse. She is tricked by Cesaire with the portrait of a young man (Viktor von Staal) which is presented to her as that of her future husband. But when Madelone discovers this scheme she flees, again in men's clothing. But on her route to escape, she meets the young man from the portrait and falls in love with him. But Madelone can't give up her disguise right now...
Prague in the 1860s: Balduin is a popular, handsome student, the best fencer in town, in amicable rivalry with his friend Dahl for the affections of Lydia, the innkeeper's niece. While the students are celebrating Lydia's birthday, the opera singer Julia Stella arrives at the inn - and Balduin's life begins to unravel. He is immediately infatuated with the glamorous singer - but she is already kept by an admirer, the wealthy and foppish Baron Waldis. How can a poor student hope to compete? The mysterious Dr. Carpis, who also has ties to Julia and is jealous of the Baron, intervenes. But the price will be higher than Balduin can ever imagine. He risks his sanity and his life - perhaps his very soul - haunted by his own reflection.