(SPOILERS!! more for previous films though)
Although I've seen both versions of this, for the purposes of this little post I'll be focussing on the theatrical cut which I re-watched recently. For the record, I also prefer this cut.
The first three Alien films, literally follow on directly from one another. Following Ripley's story to it's conclusion.
In this one, the EEV containing Ripley, Hicks, Newt and Bishop, crash lands on Fiorina (Fury) 161 a prison planet. They're found by the resident inmates and taken in. The reason for the crash is a fire that broke out onboard the EEV (guess what started that! It's in the opening credits and pretty obvious!!).
After Aliens' whole hive, we're back to just the one, not that that's a good thing for the characters as one's bad enough!
A lot of people don't like this one (or Resurrection for that matter, but that's a different post!), I do! I really like it, I love the premise of the prison, the characters that fill it and general plot. The only bad thing for me is the hokey (using that too much) CG Alien, the tech wasn't quite there at this time, probably could've done with more man-in-suit-in-shadows.
Despite all the trials and tribulations, David Fincher pushes the envelope to create a beautifully atmospheric film and worthy addition the the Alien line-up.
Alien3 - 9/10
Alien3 - 9/10