The film begins on board an escape vessel in which Ripley, Newt, Hicks, and a droid called Bishop are traveling on. The pod crashes on a planet inhabited by prisoners who have been left to govern themselves in a facility, killing Newt, Hicks, and destroying Bishop. Ripley is revived from her cryo-sleep from the prison doctor and soon discovers what happened to her and her remaining crew members. After calling for assistance from the Company they wait for Ripley to be transported off the planet, as she doesn't belong there. After a short time, a shaven-headed Ripley starts discovering that prisoners are being killed in a very similar manner to that of the Aliens she has faced in the previous two films. Once this is discovered, she and the remaining prisoners must devise a plan to kill the Alien that stalks the prison facility, hiding in ventilation shafts. However, she soon discovers that that it isn't the only Alien on the planet. There is also a Queen, but where?

Multiple proposed scripts caused misleading advertising which implied that the movie would be set on Earth. William Gibson also drafted a script in which Ripley spent most of the film in a coma.

Dillon:
You're all gonna die. The only question is how you check out. Do you want it on your feet? Or on your fuckin' knees... begging? I ain't much for begging! Nobody ever gave me nothing! So I say *fuck* that thing! Let's fight it!

Continuity: Dillon's glasses disappear after Golic frees the alien.

Written by Rick Evans