Links: TVTropes (entire series), Wikipedia, IMDB (8.5).
One of those rare moments when a sequel equals or exceeds the already-esteemed original. Compared to Alien, this film shifts genres toward more of a sci-fi action/thriller. The plot is gently interwoven with a subtext drawn from the Vietnam War, layered on top of the first movie's established fabric of Joseph Conrad, but even so it stands up well enough on its own without awareness of this. Also, the characters — while a bit stereotypical — gel together in a way that the first film never quite developed, and the pacing is surprisingly good when you consider how long the film is. Score: 4 stars out of 4.