What is Joss Whedon's The Cabin in the Woods about?

This mystery movie is buzzing around the geek blogs.

Everybody wants to know about Joss's creation, well, "Fred" aka Amy Acker knows and she told:

Acker let slip that Cabin in the Woods is a creature feature. "There's a lot of scary monsters," Acker said in a group interview while promoting the upcoming ABC TV series Happy Town. "It's a scary movie."

Okay, interesting... I can't wait to hear more.

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