Ye gads, this was the most painful, two-hour trainwreck I've ever watched. By that I don't mean it was a bad movie: it was a very good movie. Based on the play, this 1966 movie starring Elizabeth Taylor and Richard Burton is one of those actionless, plotless character dramas Hollywood used to make back in the day.
To be perfectly honest, I'd heard of the play (just by the title), but really had no idea what it was about. I randomly added it to my Netflix queue when it popped up while I was searching for the movie version of Mrs. Dalloway.
Spoiler: It has absolutely nothing to do with Virginia Woolf.
A New England university professor and his wife have a younger professor and his wife over for dinner. Just a nice little dinner party. The unsuspecting younger couple soon realize that they have walked into the deepest pit of married hell: abandon all hope, ye who enter here. Their hosts hate each other with the kind of hate only a long-married, dysfunctional couple that has been stewing for years in resentment, bitterness, and mutual contempt can feel. Before their horrified audience, they engage in an evening of bloody verbal and emotional knife-fighting so cruel that you begin to wish they'd use real knives and end it.
Of course, it turns out the younger couple is pretty fucked up too.
This is a dark movie: watching it is like being a fly on the wall observing four people come completely unraveled.