This is Shakespeare by way of Woody Allen. I've never read the play, so I don't know how far afield Woody goes, but it seems to be fairly well appropriated. It feels like a Woody Allen movie.
A trio of couples are spending the weekend at a house in the pastoral countryside. One of the couples is married, another is about to get married and the third aren't even considering it. Hijinks ensue. This is probably one of my least favorite movies from the 80's of Woody's.
So, in lieu of delving into what all maybe delvable in this film, I give you this nifty chart: