Monika (German: Eine Mutter kämpft um ihr Kind, lit. 'A Mother Fights for Her Child') is a 1938 German melodrama film directed and written by Heinz Helbig. The story centers on a singer who relinquishes her illegitimate daughter to a German engineer in São Paulo to pursue her career, only to return eight years later as a celebrated film star and wife of a prominent surgeon, demanding custody after encountering the child on a film set.

The actor Ralph Gregor plays "Casanova" on the stage and everyone expects, that he also lives out the role in real life. Johanna Brinkmann, known as "Joe", tries everything to make her husband jealous of Ralph. Ralph, however, is actually dating his colleague Steffie. After a fight with her, he takes off on a short trip into the countryside and there gets to know the attractive Gertrude, with whom he falls in love. In short order, he proposes to and marries her. Soon, however, Gertude gets to know Steffie and Joe, who appear to know Ralph much better than they do, and Gertrude loses it.

A sinister man instigates blackmail against the wayward wife of a banker.