An old man about to die gives all his fortune to a young beggar he meets in an Arabian town. He takes him to his house (now the poor man's property) and he strongly advises him not to open one of the doors, the seventh door. "I could throw the key into the sea" says the young lad" No use, you'd dive to get it back". The young man is curious and he cannot resist temptation: he opens the forbidden door. A strange world is waiting for him where a girl, Leila, will be his guide .

In France during World War I, Marthe waits for her husband, Jacques, while he fights on the front lines. Marthe then begins a tempestuous affair with 17-year-old François, with whom she had a dalliance before marrying Jacques. Jealous François struggles with the fact that Marthe is married, while she tries to prove her devotion to her young, hotheaded lover. Things become even more complex when Marthe becomes pregnant with Jacques' baby.

A stranger named Constant disrupts the life of Flora, who is seemingly happy with her husband Lucien. But she suddenly experiences a passionate love, taking refuge with Constant in a cave they call “home under the sea.”

A minister falls in love with a blind young woman he sheltered, but so does his son.

Pursued by the police, Saget usurps the identity of a man who was returning to his town after having made his fortune in the United States. Under this new name, he deceives his compatriots with the exception of a doctor and the savage Isabelle. During an explanation Saget understands that Isabelle secretly admires him. She denounces him and Saget surrenders without a fight. Thus he ruins all his prestige with the young Amazon.

During the 1940 exodus, a young girl takes in a baby to whom she becomes deeply attached.

June 1944, a French town towards the end of the occupation. Following several attacks perpetrated by the resistance, the inhabitants who listen to English radio are rounded up by the Germans in a prison and considered as hostages. In one of the cells are found men from all walks of life: an aristocrat, the Viscount of Saint-Leu, Doctor Noblet, a resistance fighter, Béquille the wanderer with a wooden leg, and a strange character nicknamed "Black Market". The latter arouses mistrust among the prisoners, because it could well have been introduced by the enemy.