One of the greatest and most under-rated actors of all time was Donald Pleasence.  Donald Pleasence could do it all:  from Shakespeare to an episode of Columbo, he brought the same understated panache and elegance to every role.  

Which is not to say that he some some sort of stuck-up, prissy formal actor of the old school.  He was working class, and a veteran of World War II.  In fact he was captured by the Germans and held in a POW camp until the end of the war (and one of his later greatest roles would be that of a near-blind POW in The Great Escape).  

He may be best well known for playing Blofeld in You Only Live Twice (it is he whom Mike Meyers is imitating as Dr. Evil in the Austin Powers movies), or perhaps as the psychiatrist in the Halloween movies, but these roles were just a fraction of the literally hundreds of parts he played.  He was bald and had a big nose and a slight build but he also had intense eyes and one always got the sense that there was a smoldering red volcano just behind those grey-blue orbs.

 My favorite role of all the roles he played was in an Australian movie from the early '70's call Outback.  It's the story of a newly graduated teacher who thinks he's going to teach in some swank school but instead ends up in the middle of a desolate small town in the Outback.  There's nothing to do there but drink and debauch, and drinking and debauchery soon begin in earnest. 

Donald Pleasence plays a dissolute alcoholic doctor who's lost his license to practice medicine and so who spends his days self-destructing with beer and bile.  In one particularly memorable scene Pleasence's character is trying to explain how when one swallows it is not gravity that causes the substance to go to the stomach, but the muscular action of the esophagus.  To prove this he stands on he head and chugs a beer.  He (Donald Pleasence, in a supreme example of method acting) gets most of the beer down and then throws it all up out of his nose.  Bravo!  Perfect!

He could out-act Olivier in my mind, but try to find an example of Olivier throwing up a beer through his nose (not that it never happened) .  Donald Pleasence:  acting genius.