my idea for a fifth

Maybe it's duhm to you, whatever, not meant to be that serious. Just what I think would be cool. The first commented on the genre, the second on sequels, the third on trilogies, the fourth on reboots/remakes. I think a potential fifth could comment on celebrity culture, especially in the reality TV arena, as well as franchises that go for too long and recycle things, such as the cast. They could also make it have time travel, as Jenny stated the 5th Stab did, making it "by far the worst," giving this one low aspirations to live up to. What would make this notable would be the feat of having all the surviving cast return. All of them, not just the core three. Say the sorority sisters and cameraman from the second, Randy's sister, Kincaid, and so on. And have them interacting. And have it come out that Sidney, Gale, and Dewey have been the real killers all along, and the four movies from their perspective are their cover-up story. I know, kind of silly, and flawed, but I bet most wouldn't see it coming ;)