Deliberate mistake: After Ash's body is incinerated, the interior walls of the Nostromo appear more metallic and grey than they were before. According to Ridley Scott, this was done deliberately to make the alien's presence appear more menacing.
Alien (1979)
1 deliberate mistake - chronological order
Directed by: Ridley Scott
Starring: Sigourney Weaver, John Hurt, Ian Holm, Tom Skerritt, Harry Dean Stanton, Yaphet Kotto, Veronica Cartwright
Continuity mistake: In the shot of the alien's tail wrapping around the back of Lambert's legs right before it kills her, the floor is different to what it was before, there is water suddenly falling from the ceiling when there wasn't before and her trousers have changed from white to blue. This is because that shot was originally intended to be used when Brett was killed.
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Question: Question about the Director's Cut of the film. The scene where Brett is looking for Jones has been altered slightly - when he looks up at where the water is dripping from, you can actually see the Alien hanging motionlessly from one of the chains. Has Ridley Scott given an explanation as to why he added this new dynamic to the scene? It's easy enough to speculate why, but a link to an 'official' explanation would be appreciated.
Answer: According to the commentary on the DVD, Ridley didn't add this scene to the original cinematic release because he thought it revealed the true horror of the Alien too soon in the film. The scene is quite early in the film and he thought revealing the fully matured Alien at that time would reduce the viewer's fear.
I had watched Alien several times before I noticed the Alien hanging there.At this point the Audience have no idea what the Alien looks like, they're looking at pieces of science fiction equipment put in by the production crew that they can't relate to, so for all they know the Alien could just be a piece of kit hanging there.