Young Frenchwoman Mathilde searches for the truth about her missing fiancé, lost during World War I, and learns many unexpected things along the way. The love of her life is gone. But she refuses to believe he's gone forever — and she needs to know for sure.
The year is 1898. Héloïse, 9 years old, comes from a family belonging to the anti-Dreyfus and anti-Semitic Parisian high bourgeoisie. In a spirit of revolt, she begins a love affair with Maxime, a young Jewish journalist. During a terrible quarrel with her father, the latter suffers a stroke and dies. To get her away from Maxime, her mother Mathilde and her cousin Olympe take Héloïse on a trip to the Orient. After Cairo and the Pyramids, they go up the Nile and cross the desert in a caravan.
Without warning, Mélie disembarks on the cargo ship where her father has the sailor's blues. He remembers his drifts and his friend Max who used to get him into some crazy situations. He remembers Alice and Luc whom he decided to avenge. He has his grenade ready. But Melie has just arrived.
Nathalie, traumatized by the death of a child she had to look after, is hired by Marti to take care of the little Serge, his son. The boy is abnormal, immured in silence. Nathalie brings him out of his shell and becomes attached to her protege. She feels his life is threatened: serious incidents happen. For Christmas, they are alone, and the child mysteriously disappears. She discovers him in the basement, locked up in a chest.