Consumed with grief and a silent rage over the loss of her teenage son who was killed in a hit-and-run, Diane, the devastated mother, takes the ferry across Lake Geneva to the spa town of Évian, in a desperate pursuit of the truth. Once there, the tragic mother armed with a well-concealed handgun and a graphic, yet incomplete description of the offending car will soon suspect that Marlène, the cryptic middle-aged salon owner, and her boyfriend, Michel, are somehow involved in the irremediable act. However, the path towards justice can be treacherous and serpentine, furthermore, will it make any difference finding the culprit behind the wheel?