Hochzeitsnacht im Paradies (1962)

Operetta star Ulrich Hansen wants to return to his original profession as a doctor and announces his engagement to Regine Röders, the daughter of an industrialist, at his farewell performance. His stage partner and former girlfriend, Ilonka, isn't about to accept his decision to marry another woman without a fight. Jealous, she hatches a plan to prevent the wedding. Ulrich and Regine marry as planned and go on their honeymoon to Venice. Ilonka follows the newlyweds to Venice with her new admirer, Gustav Säuerling, and continues to try to break them up.