Arlette and her brother are penniless orphans; as the man is to leave for Africa to work for a long time, the young girl is forced to live with her cousins, four spinsters, who place virtue over everything.

An assistant pharmacist in the South of France , Blaise works for Mrs. Pinède, a well-endowed hot-blooded woman who has developed a crush on him, and her husband ... who hasn't! One day, Blaise meets Felloux, a rich man who is convalescing in Cassis. Felloux takes a liking to Blaise and decides to offer him a perfect day in Juan-les-Pins. Gambling in the casino, Blaise wins an astronomical sum. A new life seems to open to him but not for long. Indeed he loses all, but not before he has given a beautiful necklace to a young woman.

Following a broadcast on the radio, each of the listeners remembers these "little nothings" (the title is borrowed from a play by Mozart), which have often changed their lives. Each of these stories told will prove that a tiny detail in life can change an entire destiny.

Hector and Odette Dupuis' car breaks down in the middle of nowhere, but not far from a luxury hotel. The couple are well off but, being miserly, Odette is determined to keep her budget tight. Fortunately for her, the hotel offers rooms for domestics costing only 35 francs, so she decides to pass her husband as her chauffeur. As far as she is concerned, Odette presents herself as Baroness de Garches and takes a 250 franc room. But their stay soon becomes complicated. For instance, Palureau, a widower with five daughters who is planning to remarry, starts courting the 'baroness'. And that is not all since at the same time Angèle, a chambermaid, makes advances to Hector ! To make matters worse, Ferdinand, Angèle's boyfriend, decides to get even with Hector, his 'rival'. The jealous guy steals a jewel from a guest and has poor Hector accused of the theft.

1940 film by Yves Mirande

Lucie turns the house of chic dandy Gaston upside down.

Early in the war, a group of women decide to help the soldiers in the war front. They enlist the help of the wealthy Madame Marion.