Five government contractors wake up to find themselves contained under the infamous Area 51. They are forced to confront a sinister government experiment and a horrifying Alien host.

When Rachel is extended an invitation to stay at the camping lot (Lot 24) of her missing uncle, she is leery, but excited at the thought of spending some time away. Although the details surrounding his disappearance are sketchy at best, Rachel and her friends plan a weekend of hiking and relaxing.