Alien Resurrection

The clearest skip in the main series. Two hundred years after Alien 3 the military clones Ripley from blood residue to recover the creature she died to destroy, and the result is a film that nothing before it leads to and nothing after it continues. No later entry references it. The prequels ignore it, Romulus ignores it, and the television series is set two centuries earlier.

It is also the strangest thing here, which is why some people love it. Jean-Pierre Jeunet directs it like a European comic: wide lenses, grotesque faces, a crew of pirates played broadly, and a tone that slides between farce and body horror without warning. The script is Joss Whedon's, and the gap between what was on the page and what reached the screen became a long public argument, with Whedon maintaining that his lines were delivered and his scenes staged in ways that drained them. Watch the basketball scene and the underwater chase and you can see two films fighting each other.

The Ripley of this film is not the Ripley of the others, and that is deliberate. She is a hybrid, faster and crueller and faintly amused by human beings, and Weaver plays her as something enjoying itself. The one genuinely unsettling sequence has her find the earlier failed clones of herself, and it is better than the film around it.

Skip it on a first pass. Come back if you have seen everything else and want the series at its least disciplined, or for the 2003 longer cut, which opens and closes differently and is marginally the better version.