A widely underrated movie.. - spoilers.

Rating: 8/10 (2 December 2003)

Most filmgoers and critics bashed this movie mainly because of the way it was breaking from the overall climax of Cameron's Aliens. There are no space Marines that get trapped and killed one by one, no big spaceships and we're being only served one single Alien monster, which is just a boring "male" one, instead being of the scary mother of the last film. But seeing this movie in comparison with its predecessor, many years after it was made, reminded me that what makes an horror flick (in this case a space horror flick) effective is not a mountain of gore and big budget effects, but the intimate and realistic atmosphere of true terror. That's why after 17 years, Aliens looks more like an average sci-fi action movie with horror elements, in the likes of Predator, than the great horror film Alien was.
Alien 3 reprised the same idea that was so great with the first film of the series (the greatest of all the bunch, as it was a truly original achievement): a bunch of almost ordinary people left on their own, billions of light years away from their home, bound to DEFEND themselves against an evil they can't understand. Their loneliness into an harsh, foreign universe, and their lack of ability to defend their lives against the creature was creating an eerie and tense atmosphere that was truly terrorizing. Both movies were VERY pessimistic overall, in a dark way, and that's the main reason why they were effective. Whenever if its into the cargo freighter of in the abandoned detention facility, you just don't hope that something like an alien appears, 'cause the people that are there are all but prepared for such danger... They can't even handle their own problems, so how can they face a threat from outer space??? With a pro-military perspective in Aliens, where the intelligent warmhearted, soldier survives all along with Ripley, and the aliens get annihilated by a nuclear explosion, the pessimism was somewhat watered down for a more family-friendly plot with good feelings and hidden chauvinism. Of course, on the visual effects side, Alien 3 was not the best of the bunch, but it was a more intelligent horror film in many ways than its predecessor, and that's where David Fincher drew his first landmarks as a master of dark and pessimistic films, by using schizophrenic lighting and photography, dramatic soundtrack, and grotesque, barbaric characters that were adding much to the depressive atmosphere of the whole film.
And about the ending, it seems that some people just did'nt get it, and its a shame. It gives a brillant reflection on the odd fate of Ripley, as someone who's hellbent on always having to face an evil that only she can really survive, and now that she finds its actually inside of her, that's obvious that the only good way she can end this madness is by "going to hell" with it. There's this nice symbolism implying that this whole alien thing might just be the result of her own sickness, after all.