L'Amour (1984)

By spending his money buying affection from his younger wife Gloria, businessman Vince Brewster can't pay alimony. Therefore, his former wife Ellen and son Mark simply enter unseen with their luggage. Ellen uses this to peep on Vince and Gloria, imagining herself back in Gloria's place. The diner waitress Pam Wilson, who hit on Mark in her diner, then calls him over. It turns out she wants a bedroom date but even more so a bathroom one. Meanwhile, Vince's lawyer and friend Jerry enjoys his own younger lover Stacy. Ellen officially dates Jerry, admitting it's partly proving Gloria she wants sex with Jerry, not Vince. Ellen helps Gloria who falls in the pool, and the two make passionate amends. Vince and Jerry get picked up in a bar by Samantha and Leslie. The fun lasts until Vince's date reveals being a transsexual. Mark brings over Pam, but during the night painkiller-high Gloria accidentally stumbles in and has sex with him thinking he's Vince. Instead of stopping her, Mark even takes his stepmother from behind. Pam does the same to his father, only on purpose. With drunk Jerry sleeping over, Gloria visits him in bed the following morning saying they should have married. Sensing this, Vince re-proposes to Ellen.