Simple and well acted, it has tension enough to knot the stomach.

I gave this film a 9 out of 10, because it was exactly what I expected it to be.

A film with more than the usual spoiler issues. Talking about it in any detail feels akin to handing you a gift-wrapped present and saying, "I hope you like it -- It's a thriller about a diabolical secret experiment."

The biggest problem with this movie is it’s a little better than you think it might be, which somehow makes it worse. As in, it takes itself a bit too seriously, which makes most of the movie feel kind of dull.