4. John Merrick (The Elephant Man)
The make-up effects used in David Lynch's The Elephant Man were so good they actually prompted the creation of the Academy Award for Best Makeup and Hairstyling. Designed using casts of the real John Merrick's body, the makeup was carefully crafted to be as realistic as possible and played a big part in the success of the movie.
However, Sir John Hurt, who played the starring role, really suffered for his craft while filming this picture. At one point, the late actor even said the production had actually made him hate his profession. He'd have to arrive on set at 5 in the morning and sit still for 7-8 hours while the makeup was applied.
When filming wrapped up for the day, Hurt would have to hang around for another couple of hours while the makeup was removed. The whole process took such a toll on the actor he was given every other day off to recuperate. His hard work did at least pay off with an Oscar nomination.