Mistakes

After Ripley fails to shut off the auto destruct sequence, she runs through a corridor filled with gas. As she exits from the gas right before the shot cuts away we see her pass by a full sized light. Beside this light is the clear arm and head of a lighting crew member. (This is acknowledged on the DVD commentary). See more...

Trivia

Originally the design for the alien called for it to have pulsing brains in its head (the idea being so we could see the creature 'thinking' while it moved around). The effects department accomplished this by having live maggots placed underneath the transparent dome on the head. Unfortunately the maggots refused to wriggle and move around on command, so the effects dept. doused them with LSD right before the cameras started rolling. Sadly the idea was later scrapped. See more...

Picture