In 1946, many war orphans had to fend for themselves. This was the case for Renée and François, whose parents died during deportation; the two children survive by street singing. They are taken to the police precinct by a policeman and undergo medical exams and administrative paperwork. A truck takes them from Paris to Sèvres, where they are taken in by a mutual assistance home. Life there is organized in an independent republic; adults look after the young, and a civic sense is instilled in the children. François, who does not take a liking to confinement, at first wants to leave, but when he sees how enthusiastically his sister directs the choir he decides to stay. A school based on teaching through interest, attention focuses on maximizing and perfecting the interests of each child. The elder class welcomes actress Madeleine Carroll, who recounts her attachment to her country. A dance performance is organized in her honor in a nearby clearing. The guest is able to observe the positive effects of this method of education.