The Magnificent Sinner

The Magnificent Sinner (original French title: Katia) is a 1959 French historical drama film directed by Robert Siodmak. Adapted from a novel by Princess Marthe Bibesco, it is a remake of the 1938 French film of the same name starring Danielle Darrieux. The screenplay was written by Charles Spaak and Georges Neveux, and the film runs about 93 minutes.

The film portrays the romance between Tsar Alexander II of Russia and the young schoolgirl Catherine Dolgorukova, who first became his mistress and eventually his morganatic wife. Romy Schneider stars as Katia opposite Curd Jürgens as the Tsar, with Françoise Brion, Pierre Blanchar, Michel Bouquet and Gabrielle Dorziat among the supporting cast.