In a film thet stirred up the censors, Marlene Dietrich plays a lusty gypsy named Lydia, whose caravan makes a romantic refuge for Britsh agent Ray Milland.
Escaping from the Nazis, Agent Ralph Denistoun (Millard) and his partner arrange to meet in Stuttgart to purloin Hitler's posion gas formula. On the journey, Denistoun meets Lydia, whose uncanny knowledge of the Black Forest keeps him out of harm's way. Disguised as a gypsy, complete with glistering golden earrings, Denistoun arrives at the designated meeting place, which is glutted with Nazi soldiers. Only with the help of the extraordinary gypsy woman can he finish the mission that will make him a hero.