10 of the Most Memorable Betrayals in Movies
10. Ash - Alien
Okay, Ash was an android, so technically he was just the product of cruel intentions. Still, the science officer was probably taking things a bit too far when he turned on his faithful crew for the sake of promoting the existence of an alien species. Moreover, Ash's betrayal is two-fold: firstly he breaks quarantine procedures by allowing an infected crew member back on board, and secondly, he attempts to kill Ripley by stuffing a rolled up magazine into her mouth.