This better-than-average aliens flick almost works in spite of a heroine who seems to exist solely to let out ear-piercing screams at the slightest provocation. It's a little more thoughtful than its peers, which are mostly about figuring out what mundane weakness invading aliens might have before they succeed in conquering the world. In this one, it's tough to say exactly what the aliens are doing here and why; the movie is more about us, rather than them, and how we respond to things we don't understand. The message is simple and pounded in with a sledgehammer, but that's not to say there aren't moments that work exactly as intended. But the characters, all cardboard cut-outs, fall short of the mark.