Shocking! (1976)

As the world slides to nuclear war and bombs explode in the background, Juliette and her husband, Alex have their family problems, but become increasingly uninhibited. Juliette is uninterested in Alex. Armelle is in love with him but he won't look at her. She spies on her flatmate having sex with a man, then kicks him out. Alain, their son is caught masturbating by his tutor, Patricia, but she undoes her dress and masturbates as well while remembering an encounter with Thierry on a yacht. There is a dinner party and Juliette cools herself against a fan, revealing her knickerless state. Alain is caught masturbating under the table cloth and sent off to bed. Then the rest of the party adjourn to watch a porn film. Alex is turned on enough to begin to grope Patricia, and she remembers a threesome with Thierry and another male. Armelle almost masturbates and then, disgusted as the porn film reaches the point where two girls take a facial, she rushes to the bathroom. Alex goes to console her and she offers herself to him. Back in the main room Juliette and Patricia have leapt on Richard, Alex's colleague. Alex and Armelle join in and Arnold, the butler is conscripted to make up the numbers.