A few years ago, Isabelle Leritz, a famous pianist, suffered a fit of madness, in the middle of a concert. Now recovered, she fell in love with Jacques whom she plans to marry. She does not know that he is having an affair with Caroline, his sister, director of a fashion house.

Story is primarily based on the adventures of Antoine, a young telegraph messenger on his second night of work. He is given three telegrams, one of which is for the president of the Camber of Deputies. Excited, Antoine runs his bicycle into a truck and loses the telegrams. What follows is an amusing and agonizing search for the missing messages. He is assisted first by a glum, wise-beyond-her-years little girl, Amelie; an off-duty police superintendent, a schoolmaster, a cookie-tin maker and a fireman. The harmonica musical theme is played by Flore Falvey.

A schoolboy remembers his last holiday in the big house of his family in the country, before it was sold.

Sigrid and Yann are cousins, and in love with each other. A medical student, Jean marries Léna, who gives him a child, but he dies accidentally. Desperate, Yann finds Sigrid in their childhood home in Savoy. Afraid of seeing their passion revive, he decides to leave with Léna for Africa.

The invincible bandit faces his daughter, courageous and honest, who wants to end his criminal activities. With a young journalist, her fiancé, she discovers his hideout.