Instead, you get a movie that's enjoyable enough, but leaves you feeling like it could have been much, much more.

It's an amazing and heartbreaking story.

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."

While it doesn't offer any answers, it both thrills and makes you think.