Lack of good storyline.

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

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.

While it is a pity that the story wasn't told with more visual finesse, this is trivial compared to our real-world problems. It takes a good movie to put that into perspective.