One of Ridley's best - Spoilers

Rating: 9/10 (28 April 2003)

This science fiction horror takes place on a "Space Ship" named "Nostromo" with a fantastic cast and one of the greatest directors of all time. Made in 1979, this is a timeless classic that will go down in movie history, matched only by blade runner in its stunning visuals (for its time).

the film is clever in its depiction of the various crew members, in the early stages of the movie, the audience is led to believe that the ship's captain, played to perfection by John Hurt, is the hero. Perhaps at one stage we are even led to believe that Ripley, Sigourney Weaver, is the films antagonist, placed on the ship to obstruct the other characters. by attempting to keep a fellow crew member off the ship because of the rather petty issue of an unknown alien species attatched to his face (sarcasm by the way) , however after the death of the crew member and the subsequent escape of the "chest burster" Ripley is proved to have been right all along, and so, the rest of the film is spent trying to kill the now fully grown Alien, in vain. however ripley manages to finally blow it out of the airlock at the end, suprisingly enough, but not before rescuing that "stupid cat" of course
though this is quite obviously a typical Hollywood film, some viewers still manage to not understand, and so for those people, mentioning no names; the Alien species reproduce by a queen Alien being empregnated by a worker/soldier alien (not dis-similar to a bee), the queen soon lays eggs, from these eggs hatch "face huggers" these clamp on to the faces of any unsuspecting species that happen to be walking past, these face huggers lay yet another set of eggs in the body of its victim, from this eggs comes another alien in the form of a "chest burster" this then grows up to become either a worker/soldier alien or, in Ripleys case (spoiling Alien 3 for anybody), a queen alien.
as for the reason why these aliens run around killing people, one possible explanation can be found in the film Predator 2, at the end of the film an Alien Skull can clearly be seen in the display cabinet of the predators ship, one theory is that the Alien species was created by the predator species for hunting...but thats just one theory