Find a late 70s movie by describing the plot
I'm looking for the title of a movie I once saw on late night cable around 1979-80. Here is the plot:
There is a husband and wife who take a trip on their yacht (or large sailboat). They also have a small dog on the boat. While out in the waters, they come across another couple (man/woman) in a smaller boat. They seem friendly, so the husband welcomes them aboard.
Once aboard, it is revealed that the woman (from the smaller boat) is actually a man (transvestite?? ). They take the husband and wife hostage and kill the dog with a spear gun. I think they knock the husband unconscious and then abuse and humiliate the wife.
Finally in the end, it is revealed that the husband had hired these other men to do all this. The movie then proceeds to show us three alternate endings.
1. the husband pays the two men and they leave the boat
2. the wife (after learning about her husbands plot) leaves with the other two men
3. the wife kills her husband with the spear gun.
If anyone knows any more information about this movie, that would be great. I would like to see it again to see if it was as interesting now as it was then.
