Sweet Evil (2010)

Original title: L'enfance du mal

Fifteen-year-old Céline knows more about life than is appropriate for her age. She wanders the streets, surviving, with the help of her boyfriend Romain, thanks to her defiance and ruthless practicality. She secretly sleeps in the garden house of a luxury villa, where one evening she is discovered by the owner, Judge Henri van Eyck. Despite his wife Nathalie's reticence, he takes the girl in and Céline gradually gains their goodwill and affection. The fragile balance of their mutual trust, however, comes in serious jeopardy when the web of lies the girl has told her protectors begins to unravel, revealing her real motives.