Malibu Days, Big Bear Nights(1982)

The discovery of a stag-flick in the closet of their rental ski cabin gets four college buddies so worked up they forget all about skiing. Once they've watched the likes of J.W. King, Nick Rodgers, Giorgio Canali, Jamie Wingo and Mark Scott Solo doing everything in the book, the four college pals turn their attention towards each other and end up in four-way action that literally never stops!