A Classic in Both Horror and Sci-Fi Genres

Rating: 9/10 (28 August 2007)

After landing on a planet to perform a rescue, a group of military excavators find an alien life form that isn't exactly friendly. Face hugging, chest popping and outright carnage ensue, as one by one the crew is left to fend for themselves.
This film goes down as a classic, and it well should have. A giant in the sci-fi world directed this (Ridley Scott, "Blade Runner") and it was written by Dan O'Bannon (who also adapted "Total Recall" from Philip K. Dick and wrote/directed the horror classic "Return of the Living Dead"). And a cast consisting of Sigourney Weaver and Ian Holm? Amazing!
What makes this film great is the real sense of being alone it leaves you with. Even when the crew is grouped together, they know they're trapped millions of miles from home. They must fight to survive, no running possible. The enemy changes and remains unknown, and even one of the crew may not be on their side.
This film contains the iconic "chest-popping scene", which was pretty cool. Granted, after seeing "Spaceballs" you might be let down by the version in this movie, but it's still pretty memorable. The face-huggers are also creepy, if you can imagine what that must be like to have a slimy, acid-blooded creature suctioned on your face, dropping eggs. Nasty! The film goes from sci-fi to horror and back again, mixing the two together in way that's rarely successful (although I would give a nod to "Event Horizon" for being a fine exception).
They implement the "final girl" scenario well. I don't mean to ruin the plot for anyone, but not many of the crew survive and one of them is Sigourney Weaver (which I suppose is obvious since she's in all the sequels). She knows how to be tough, even if she's not exactly pretty while doing it. (I think horror fans crave attractive women more than science fiction fans do, if this film is any evidence.)
My only complaint with this film is the alien suit, which seemed too rubbery and human-like. Luckily, the director was smart and saved the reveal until much later in the movie and kept it to a minimum. Sometimes the unseen is scarier than the seen, especially if you aren't able to make the monster as scary as you planned (which is fixed in future sequels).
If you haven't seen this one, see it. It sets the bar for all future science fiction films, particularly ones involving hostile alien life. I don't know if a film in the genre can be made any more without somehow paying their respects to this one.