I remember a movie (or I suppose it could be an episode from one of the many many softcore series that used to show up on late night cable) where a husband and wife are in a large mansion. I can't really remember why. Unexpectedly a woman shows up who has some business there. Eventually they all have a threesome. Later the woman's boyfriend shows up. The husband and wife were clearly not expecting this. The boyfriend expects to have sex with the wife (a little tit for tat if you will). I remember there was a slight tinge of malice here. She wasn't forced, but seemed a little nervous and or reluctant. The woman and Husband watch the two of them having sex by the pool in and around the hot tub. I've been wracking my brain and searching online, but I've come up empty. Any help would be greatly appreciated.