After ten years abroad, Catherine returns to Luxembourg to catch up with her daughter Alba, brought up by Catherine's mother Elisabeth. She then kidnaps Alba and takes her on a trip to a lake up North.

Single mother Elaine is disturbed by her son Martin's aggressive behaviour, she visits his late father's estranged family in small-town Luxembourg, which hides a much darker nature. When she realizes that Martin could become like them, Elaine is forced into a desperate fight for her son's future.