The beauty of horror movies is that the bad guy can be anyone or anything. There’s no limit to who can turn into a villain and when they might go off the rails. Over time, films in this genre have excelled at making someone you’re supposed to trust turn against you, and it's possible they've been most successful in this regard with doctors. Evil or possessed doctors are so scary because the protagonist usually starts off having an unwavering belief in them -- after all, who doesn't trust a doctor?! -- just for that to be taken advantage of. There’s an aspect of blind faith when dealing with a doctor or a scientist; they’re supposed to be the good guys. For the movies on this list, the opposite is true. Here are the 11 most horrifying doctors from cinema’s past (because 10 just isn’t enough).