Cabin in the Woods, historical AU! (Also, your username is presh.)
Oh man... I'd probably make it a Western and give the technicians and facility a really steampunk perspective technologically speaking. Instead of going on vacation to a cabin the group would be heading out to check an as of yet uncivilized area to see if it's a good place for expansion, or so they would think. They'd actually be sacrificed by their town for the sake of appeasing the Ancient Ones. Curt would be the charming and charismatic son of a wealthy cattle rancher, Jules his fiancée, Holden would be the town's doctor-in-training, Marty is the sheriff's layabout son, and Dana is the preacher's daughter. (They'd still have their personalities, but this would be how the town defines them and why they are selected for the ritual.) They'd be surprised by finding a Cabin and would decide to rest there for the night. Everything would follow fairly similarly, except some horses would die too. Poor horses.
As for a title I think I'd go with... History Dooms Even Those Who Can (as a really obnoxious reference to the idea that those who can't learn from history are doomed to repeat it)
