In 1939, the "Union des Jeunes Filles de France", a French communist movement, sponsored this documentary short constituting a tour de France of farms, factories and workshop where young women work, thus taking charge of their own destiny.
Jean Bonnefoy, who has a talent for singing, is unemployed. So he is very happy the day he is offered a post as a music teacher in a college for young women. But he soon realizes the job is only a mixed blessing as a group of girls have set about making life tough for him. Among them is Anny Laforcade, a student who finally changes sides, taking pity on her teacher and falling in love with him. At one point, Jean meets Zébulon, a talent agent who decides to launch his singing career. Zébulon has a far-fetched idea: He asks Anny to disappear for a few days thus making people believe that she has committed suicide out of love for Jean. The latter, who is not aware of the scheme, is devastated.
