Sounds like the same movie... You're right the people are already dead, but some don't realize they died. In particular, there's a couple of recently deceaded guys that stand get up right after they died, not knowing they died... They start complaining about muscle aches,labored brething, etc... After a bit someone notices the bruise like spots in the guy's legs from the blood pooling there. They two dead guys are get pretty bumbed when they're told they're dead then start trying to eat everyone... ...Or, this could be the result of a bad memory... It has been twenty years since I've seen the movie.