Hugo Weaving as Agent Smith.

Arnold Schwarzenegger as The Terminator.

Rambo_1923:
No one else can be Terminator!

Kathy Bates as Annie Wilkes in 1990 film adaptation of Stephen King's 1987 novel "Misery".

mohksinats:
Just rewatched this at the local theater recently, and she is the reason that film holds up to this day.

Alan Rickman as Hans Gruber in Die Hard.