5. Ash Is An Android - Alien (1979)
Being the first in the series, we had no frame of reference of what to expect from this film. When we find out Ash is an android, it comes completely from left field. We didnt even know that it was a possibility; we were too distracted by the monster alien stomping around the premises. Its really a backdoor mind-bending moment. Ridley Scott is throwing so many different fazes of the alien at the crew that corporate intervention via robot wasnt on the radar. But besides the brilliant double-cross by Ash, the execution of the moment is of sci-fi legend. The now iconic white blood of the android, sticking the porno mag in Sigourney Weavers mouth and his room-trashing freak-out are all features of the crazy scene that leave us all as stunned as the crew.