Four times the Alien-fest

In the Alien Quadrilogy we see the first contact right to the very end of the conflict between the Aliens and Mankind.
Deemed as one of the most influentical and thrilling horror'alien series of all time this is a must for anyone who loves a good bit of Extra-terrestrial action.
The defining work of actress Sigourney Weaver is displayed here as well as Ian Holm in "Alien".
Many spin offs have been made, for instance Alien vrs. Predator, however, these four original titles far surpass the excitement and horror of their sequels.
An excellent buy all round.