Director Paul Thomas is at his best when he works from scripts that put characters in situations where they're freed of conventional roles and standards of behavior and are able to explore their sexual impulses. In Shipwreck, sexual impulses become a means of survival.
Tony G.'s script uses a time-honored plot structure. A group of passengers was up on a deserted Pacific island after their sailboat goes down in rough seas, the captain and crew included. Jon Dough plays the only crew member to survive, a brutal, overbearing guy who quickly alienates the other passengers with his thuggish actions. Mickey G. plays a conservative character in direct contrast to Dough. Marc Wallice is somewhere in between, though he's never the psycho Dough is. Each manages to have sex with at least two of the girls during the course of the film, but the emotions driving each sex scene and the different partners constantly shift, as everyone navigates their survival. The women's characters range from the retiring Missy to the defiantly feminist Stephanie Swift to the calculating Deva Station. Lexus and Alexandra Silk, on the other hand, give free rein to their unbridled sexuality.
The ending is a bit contrived, but that's a minor point. Shipwrecked is another example of Thomas at his psychologically-probing, adult best.