In France, the single translator Diane Siprien adopts an Asian baby named Liu-San in a foundation directed by Sybille Weber. Years later, a weird mark appears on the boy's chest and Diane and Liu share their dreadful nightmares. Diane is assigned for a three-day job in Germany and she leaves Liu with her friend Sybille. However, while going to the airport, Diane finds Liu hidden in the backseat and startles with an eagle flying toward the windshield, crashing her car. Liu falls into a coma and his digital recorder records the boy speaking in an unknown dialect. When Diane searches the translation and the origins of Liu, she is surrounded by mysterious murders. She discovers that the dialect is from the mystic Mongolian Tseven tribe and that Liu is a powerful Observer; further, he is in danger, threatened by sorcerers that need the boy for their Council of the Stone..

François, director of a primary school, teaches third graders. It's a demanding position, leaving him little time for his private life. But he is committed. At the beginning of the school year, his daughter has come to stay with him. Laura is 14 and has arrived from Tahiti with her mother for the first time after his separation, shaking up his calm existence. In the school courtyard, behind the playful games and laughter of the kids, their cries mask problems they struggle with on a day to day basis. Francois is more than a teacher, he's a friend and a protector.

Paul Olivier has created a parallel universe with his rules and rituals allowing him to overcome the trauma suffered in his childhood. His fate will be sealed when his path crosses with Sasha.