Mona Bergeron is dead, her frozen body found in a ditch in the French countryside. From this, the film flashes back to the weeks leading up to her...

Max, who dreams of adventures, abandons his studies at 18 to become involved in the navy. He becomes the sailor 512.

In the streets of Marseille, René Allio encounters, once again, the spaces of his childhood, and remembers his family history.