Alien 3

Skippable, and the reason is in the first four minutes. Newt and Hicks die under the opening titles, offscreen, in a crash caused by nothing anyone did. The ending Aliens spent two and a half hours earning is deleted before the story starts, so that this film can put Ripley alone on a prison planet with no weapons. Whatever the merits of what follows, many viewers never forgive that, and they are not being unreasonable.

The production is the usual explanation and it is accurate as far as it goes. Shooting began without a finished script, after several completely different versions had been developed and abandoned, including one with no Ripley in it. David Fincher was a first-time feature director with the studio rewriting around him, and he left the film before it was finished. He has never claimed it since in any meaningful sense.

What is underrated is the film underneath all that. The prison colony is the most interesting setting in the series: a decommissioned foundry staffed by violent men who have organised themselves into a religious order, with no guns anywhere on the planet because the inmates cannot be trusted with them. The creature cannot be fought, only lured, and the final act is men running down corridors as bait. No other film here has an idea like it.

If you watch it, watch the 2003 Assembly Cut. It restores about thirty minutes, replaces the ox with the dog, repairs a badly dubbed second act and ends differently. It was assembled from workprint material without Fincher's involvement, so it is not an author's version of anything, but it is a markedly better film than the one released in cinemas.

Nothing later depends on it except Resurrection, which is itself optional. If you want Ripley's story to end, it ends here, and the bleakness is the point rather than an accident.