Traumatized by the breakup of her marriage, a middle-class mother decides that a little girl who attends her son’s school is actually her dead daughter, who perished in infancy during a fire in the maternity ward. This twisty French thriller (2008) suffers from a slow start and a far-fetched plot, though it’s carried along by the steely intensity of its lead actresses: Catherine Frot (The Page Turner) as the obsessed woman and Sandrine Bonnaire (Intimate Strangers) as the little girl’s mom, who welcomes Frot into her home but grows ever more worried by her intrusive behavior. Safy Nebbou directed. In French with subtitles. 95 min.