The opening scene of this movie is pretty incredible. I've seen a number of sci-fi movies with great special effects but my roommate and I looked at each other after the opening sequence and he said plainly, "sensory overload." The plot of the movie is pretty simple but the nice thing about this sci-fi movie is that it lets the audience figure out most of the technology for themselves instead of wasting time to "subtly" explain it. The creatures in this movie are also very interesting. You don't get a really good look at them until about two thirds of the way through. Overall, a very entertaining movie.