Mistakes
In the underwater scene, Johner fires a grenade launcher at two of the aliens that are following him. Watch closely and you'll see the grenade pass through one of the aliens' head for a few frames without damaging it before exploding. Slow-mo MIGHT be necessary to spot it but ISN'T vital. It's perfectly visible at normal speed. See more...
Trivia
Both Winona Ryder and Ron Perlman nearly drowned during the filming of the underwater scene. See more...
Movie Mistakes blog
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Alien Resurrection (1997)
Directed by Jean-Pierre Jeunet, starring Dan Hedaya, Gary Dourdan, Ron Perlman, Sigourney Weaver, Winona Ryder (add more)