Hector Dumontier has had enough of his wife Noémie : she is always immersed in those detective stories he disapproves of. To teach her a lesson, Dumontier decides to simulate the burglary of their house, with the help of an alleged jewel thief masked by a hood. He creates many false leads and everybody in the house gets suspected, from Ernestine, the maid, to Cabassol, the chauffeur, to Rosine, the Dumontiers'daughter. The disorder is complete and the various police detectives in charge do not help much.
Stuck in Angoulême between her uncle, who composes classical music, and her aunt, who is a fan of contemporary music, young Irène finds life boring. Fortunately, there is swing music which illuminates her days. So when, one day, Raymond Serre and his swing orchestra come to Angoulême, she seizes the opportunity to slip the copy of a song she has written into the pocket of one of the musicians. The trouble is that while she is doing so, the train she has boarded pulls out.
Married to Karl Ammer, the station master of Thaya, a Hungarian quiet village, Anita is a pretty young peasant who feels deeply bored. She dreams of another life while watching the daily express trains to Budapest. An incident will force her to leave her province: she has to go to Budapest to attend the funeral of an aunt and receive a share of the inheritance. After completing the formalities, Anita misses the train to go back home and then she finds herself alone in the capital.
The tailors Moïse and Salomon Lévy decide to marry Mina, Salomon's daughter to a good match, to save themselves from the competition that Cohen makes for them. Mina will eventually succeed in marrying Pierre, from a marriage of love, without this harming the family business.
This French musical comedy was based on the stage play Mademoiselle Mozart, written by Yvan Noe, who also directed and produced the screen version. Danielle Darrieux plays Denise, the owner of a music shop that is facing closure. Wealthy young Maxime (Pierre Mingand) falls in love with Denise but knows full well that she despises rich folks and would refuse to accept his charity. Thus, Maxime arranges to secretly buy the store then takes a job with the establishment as a humble sheet-music salesman. When Denise finds out that her new employee is actually her boss, she is furious, but rest assured that Love Will Find a Way. The lovely Danielle Darrieux is permitted to sing on several occasions, which she does enthusiastically if not altogether expertly.