Without spoiling the film for the uninitiated (though the keyword suggests you know it), the movie is actually a brilliant deconstruction of the horror genre. Beneath the cabin lies a high-tech facility run by white-collar technicians (led by the late, great Richard Jenkins and Bradley Whitford) who are manipulating the teenagers' environment to fit classic horror archetypes.
The Cabin in the Woods is a modern horror classic that rewards repeat viewings. While the temptation to type into Google is understandable (free is free), the risks outweigh the benefits. You risk legal trouble, computer viruses, and a sub-par viewing experience. Mp4moviez The Cabin In The Woods