Simone and Jean have just married and, looking for a home in the Paris region, are lucky enough to find a house with a garden in a residential suburb. Expecting their first child, the young couple began to observe how the parents of neighboring families were raising theirs.

1920, in a small village in Provence. Monsieur Pascal, a young schoolteacher, is faced with a lack of interest from his pupils. He decides to radically change the methods employed by his predecessor. He listens to the children, draws inspiration from their discoveries and takes them out into nature. The pupils will rediscover the pleasure of learning, and he will rediscover the pleasure of teaching. But some parents and notables don't take kindly to this little revolution.

A woman in Paris hires a taxi driver to locate her ex-lover, father to her newborn child, who left her without leaving an address.

Robert Langlois is now married to Catherine, the former housemaid. And they would live happily ever after if the housing crisis did not force them to live together with Gabrielle and Fernand, Robert's parents. For, despite the good will on either side, tension soon arises. What else to expect when there is too little space in their Montmartre apartment for four people (then for six then eight, the couple having... two pairs of twins!) ; the continued presence there of Fernand (who loves peace and quiet) after he is driven to retirement ; the difficult beginnings of Robert as a lawyer in a room of the apartment, etc... Other troubles follow and the harried family is on the verge of implosion...

The residents of the apartment building on Rue Montmartre are a motley crew of oddballs and eccentrics. The daring son of a professor couple is in love with a sexy student who supplements her pocket money by working as an au pair. And then there's Monsieur Calomel, the crazy but helpful neighbor who's always ready with a funny face...

A propaganda film of the communist party of France, showing how the comrades help the proletariat against the capitalists.