At 14, Diane is an enigmatic teenager and a loner. She is busy bringing up her little brother, Marc, and has an intense relationship with her father, Christian. The appearance of Julia, a young charismatic and emancipated English girl, in her neighbourhood turns Diane's everyday life upside down. Diane, who wants to break the bounds of childhood at any price, goes through the most dramatic experiences of her life in the space of six months. The closer she is to Julia, the more she turns her back on morality, paying no attention to the consequences or the limits of her desires....