Mistakes

In the scene where Kane is struggling on table shortly before the alien rips through his chest, if you put it in slow motion (it's probably best seen on DVD) just before the first patch of blood appears you will see his t-shirt ride up and you can see something strapped to his chest. This is some sort of pack containing fake blood that discharges on to his t-shirt. See more...

Trivia

Originally, director Ridley Scott wanted "Alien" to have a much darker ending. His intention was to have the alien get back on board the shuttle, rip Ripley's head off and then calmly sit down in her chair and record the final transmission, speaking in her voice. The producers understandably found this a little too extreme, so Scott tried changing it to having Ripley go to sleep as normal only for the camera to pull back out of the airlock's window and reveal an alien egg, in the process of hatching, attached to the outside of the shuttle (after the "Brett/Dallas egg mutation" scene was deleted, this also had to go). See more...

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