This is really high class movie and I really love it. If a movie can manage me to stay hooked on the whole movie online, that's really impressive. It's probably the most known Sci-Fi movie and it's really entertaining. Anyway, Sci-Fi may boast of one of the biggest numbers of good movies. What determines the phenomenon of this movie? It's realism, taking care of psychological probability?. Feel free to play the movie online or download it to your computer.