The Golden Mass (1975)

This erotic psycho-sexual arthouse drama with strong religious and surrealistic elements follows David and Helene, a rich unhappy middle-aged couple stuck in a stale sexless marriage who live with their numerous household staff in her family's stylish Art Nouveau chateau on the outskirts of Paris, France. One evening, they invite their circle of close and attractive friends to a dinner party that's meant to culminate with an orgiastic and ritualistic defloration of a young and willing Madonna-like nubile virgin, Marie-Odile. The lavish ceremony is hosted by Helene with the help of Raphael, the strange young Messiah of this unusual love cult whose goal seems to be to help everyone recapture their lust for life, including a possibly terminally ill young female guest there. David brings a young man called Alain to the party who, to David's dismay, quickly turns his interest towards Helene's voluptuous young female friend, Katia. Feeling emasculated and unwanted, David, who may or may not be gay, goes to bed before dinner, and Elisabeth, his jaded young daughter and the only person who understands him, helps him retire. Meanwhile, back at the party, a meek man named Pierre watches his domineering wife, Laura, and her gorgeous lesbian lover Loulou enjoying a chicken leg as well as each other. Other guests eventually become frisky as well. As the climax of the evening approaches, Marie-Odile prepares for her role in the ceremony, Pierre's attempt at a threesome goes awry, and Helene becomes the focus of a love triangle which includes her handsome young adult son, Philippe, as the two share an incestuous desire for each other, and their young affectionate maid, Rosa, who sees Helene as her surrogate mother and is apparently in love with her, even though this love is one-sided. Other guests include Philippe's possibly platonic male friend Juliene.