Les Biches
Directed by Claude Chabrol, Les Biches is a landmark in film history:  its theme of bisexuality and upper-class decadence is surpassed only by its cool precision  of cinematic style and exceptionally subtle performances.  Socialite Frederique (Stephane  Audran) encounters young student Why (Jacqueline Sassard) on the streets of Paris,  seduces her and whisks her off to spend winter with the chic crowd of St. Tropez.  When  architect Paul (Jean Louis Trintignant) meets Why, he too charms her and comes between  the two lovers.  Frederiqe then seduces Paul out of jealousy, but finds herself feeling real  love.  Paul and Frederique invite Why to live together with them, resulting in a ménage a  trios beset by jealousy, madness, and ultimately, murder.