Nice, France, the 1970s. Agnès Le Roux, the young heiress of the Palais de la Méditerranée, one of the most prominent casinos on the Côte d'Azur, mysteriously disappears. Her mother, Renée Le Roux, has no doubt that Maurice Agnelet, the family's former lawyer and her daughter's lover, murdered her to gain control of her fortune. And so begins a brutal battle for the truth.