Just to save prospective screenwriters a little time:
Four to Eight
1) Horny Teenagers
2) Horny College Students
3) Horny Scientists
4) Horny Generic Friends
head to
1) A remote cabin in the woods
2) A remote abandoned old house
3) A pleasure boat taken to a remote location/island
4) A remote archaeological dig
where they come across
1) An ancient book/scroll that says it shouldn’t be read
2) An audio tape that says it shouldn’t be played
3) A video tape/DVD that says it shouldn’t be watched
4) A button/lever that says it shouldn’t be pushed/thrown
The group jerk reads/plays/watches/throws it, and unbeknownst to them releases:
1) A horde of flesh-eating zombies
2) A horde of demons who turn people into flesh-eating zombies
3) A secret military flesh-eating bioweapon experiment
4) The incredibly vicious ghost of a spooky little girl
Meanwhile, the group:
1) Splits into couples, one of which has sex, while of the remaining couples, the males want to have sex but are ‘comically’ blown off by the females.
2) Splits into couples, two of which have sex, while of the remaining couples, the males want to have sex but are ‘comically’ blown off by the females.
3) Splits into couples, three of which have sex, while of the remaining couple, the male wants to have sex but is ‘comically’ blown off by the female.
4) Splits into couples, all of which have sex.
5) Splits into couples, three of which have sex, while of the remaining couple, the female wants to have sex but is ‘comically’ blown off by her nerdy male opposite who is engrossed by the book/scroll/audio tape/video tape/DVD/button/lever.
Unbeknownst to the rest of the group, the zombies/demons/bioweapon experiment/ghost of a little girl horribly slays:
1) A couple who are preparing to have sex.
2) A couple who are having sex.
3) A couple who has just finished having sex.
Later, the missing couple’s absence is noted but ignored, except by:
1) One girl who is laughed at by her friends.
2) One girl who is laughed at by most of her friends and comforted by one of the remaining girls.
3) One girl is who laughed at by most of her friends, but comforted by the boy she secretly likes.
4) The nerdy guy who is laughed at by most of his friends, but comforted by the girl who secretly likes him.
Later, one of the remaining people is frightened by:
1) A cat springing from inside a cabinet.
2) A cat springing from inside a closet.
3) A cat springing from inside a food locker.
4) A cat springing from inside a dresser drawer.
That night, the zombies/demons/bioweapon experiment/ghost of a little girl horribly slay:
1) A couple who are preparing to have sex.
2) A couple who are having sex.
3) A couple who has just finished having sex.
Another girl, having just finished sex, finds one of her dead comrades’ heads:
1) In the refrigerator, and is then killed.
2) In the beer cooler, and is then killed.
3) In the front seat of the group’s blood-spattered and now disabled car/van/boat, and is then killed.
4) On the shoulders of the friend’s now demon-possessed/zombified body, and is then killed.
Meanwhile, potential help seems to arrive in the form of:
1) An overbearing cop, who is killed before he or she can announce their presence.
2) A pompous teacher, who is killed before he or she can announce their presence.
3) A nagging parent, who is killed before he or she can announce their presence.
4) A snooping neighbor, who is killed before he or she can announce their presence.
Alerted to their danger, the remaining three find a recording/journal made by the now-deceased person behind all their problems, who proves to be:
1) A scholar who researched things Man Wasn’t Meant to know.
2) A scientist working on a bioweapons experiment.
3) A mad Bible-quoting preacher who sought the End of Days.
4) The tormentor and then killer of a little girl .
At this point, the three remaining people:
1) Split up to try to find those friends they aren’t sure are dead.
2) Split up to try to find outside help.
3) Split up to try to find something with which to fight the adversaries.
4) Split up to try to find materials with which to barricade themselves.
5) Split up to find materials with which to fix their disabled car/van/boat.
Meanwhile, the remaining unaffiliated male displays:
1) Cowardice, and is killed.
2) Overweening confidence, and is killed.
3) An inclination to try to escape by himself, and is killed.
4) An inclination to force himself upon the remaining female, and is killed.
Confronted, the Last Couple:
1) Manages to banish/kill the monsters/flesh-eating zombies/ghost, and leaves, not knowing that the menace isn’t entirely dealt with.
2) Manages to banish/kill the monsters/flesh-eating zombies/ghost, but are then killed before they can leave by the menace that wasn’t entirely dealt with.
3) Manages to banish/kill the monsters/flesh-eating zombies/ghost, and return to their real lives, only to be eventually killed by the menace that wasn’t entirely dealt with.
4) Manages to banish/kill the monsters/flesh-eating zombies/ghost, and return to their real lives, onto to find that they themselves are infected and become monsters/flesh-eating zombies/ghosts.
***
Hope that helps.