I tend to find performances where actors were portraying real life monster more evil.
The guy who played the child rapist in Bastard Out of Alabama and also the guy who played Harry in Harry Portrait of a Serial Killer. Those two movies really freaked me out.
When I was a kid, the other two characters I found terrifying were Maleficent in Sleeping Beauty. That witch was just pure evil. Also, I saw this movie Magic when I was a kid about a guy who was a ventriloquest and whose puppet was talking to him. Recently, I found out the actor in that was Anthony Hopkins.
Well, that explained a lot.