During a railway journey, Baron van Geldern meets Evelyne, an attractive young woman travelling in the same carriage. After the train is derailed, they spend a night together at a hotel, and the womanizer falls in love with her. Complications ensue when he discovers that she is engaged to his American friend.

Southern France, the present. About to marry, Charles Leblanc glimpses beautiful Stascha with her autocratic older companion, Karoff. They meet shortly after on a train. Stascha confesses she and Karoff murdered her husband, and asks for his help to escape from Karoff. She introduces Leblanc as her cousin, and the three go to an alpine hotel for a frantic New Year's eve party. The police arrive next morning. Karoff draws a gun and kills Stascha, leaving a distraught Leblanc cradling her body.