Nightcap (2000)

Mika, heiress to a Swiss chocolate company, is married to celebrated pianist André and stepmother to his son, Guillaume, whose mother died in a car wreck on his sixth birthday. Their lives are interrupted by the unexpected arrival of Jeanne, a young woman who has learned she was almost switched with Guillaume at birth.
Claude Chabrol, Cécile Maistre-Chabrol, Daniel Maurer, Isabelle Vossart, Aurore Pasquiss-Chabrol
Isabelle Huppert, Jacques Dutronc, Anna Mouglalis, Rodolphe Pauly, Brigitte Catillon, Michel Robin, Mathieu Simonet, Lydia Andrei, Véronique Alain, Isolde Barth, Jacqueline Burnand, François Germond, Antoinette Martin, Michel Moulin, Dorotea Brandin, Jean-Marie Daunas, Catherine Epars, Rodolphe Ittig, Nathalie Gaubicher, Sibylle Blanc, James Hauduroy, Anthony Glur, Alberto Soccorsi
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