Provence, 1847. The son of a wealthy landowner in the south of France, Jean-Baptiste, loses his mother in a tragic accident. His truculent father, who was always envious of his son and his relationship with his mother, takes a harlot he met a few months earlier as his new bride. Soon after, Jean-Baptiste is falsely accused by his "stepmother" of trying to take advantage of her. In disgust, his father banishes him forever from the family home. Jean-Baptiste's only solution is to live with Blanche, his mother's sister, in the mountains.

While she was jogging Lisa Campion , the daughter of the retired police officer Fabio Campion , discovered the frozen corpse of Julien , a child who disappeared 20 years ago.The police officer Simon Beauregard is then sent to Roches Noires , a village of the Tarentaise Valley, for the criminal investigation.