Boy and friends leave trib, are found by strange couple, couple sleep with the kids, the kids transform into enhanced humans, the couple turns on one another and start killing the kids, the boy and his girlfriend survive and return to the tribe to take more kids.

Sounds like one of the
Series of movie remakes
Inspired by Roger Corman B-movies

Teenage Caveman (http://www.imdb.com/title/tt0283043/) (2002)


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