Marlon Brando changed acting forever. That's not just flattery, it's a fact. Director Martin Scorsese said of him, "He is the marker. There's 'before Brando' and 'after Brando'."
Even for those of us who weren't around in the 1950s to see the change take place, there's no arguing with Brando's impact. He wasn't the only actor to use "The Method," but he was the one who made it undeniably sexy. Montgomery Clift and James Dean may have set us on fire, but neither had a moment like Brando's shirt-tearing scene in 'A Streetcar Named Desire,' where he drops to his knees and bellows his wife's name. In that film, he played a brute, but one we couldn't take our eyes off.
There's also no denying that the same intensity and spontaneity he brought to his craft also made him a difficult to work with. Even at the peak of his career, he was always a Hollywood outsider, forever that gang leader from 'The Wild One,' saying, "Whatta ya got?" when asked what he was rebelling against. He refused higher-than-equity wages in his first big Broadway job, just as he'd refused during his big comeback with 'The Godfather,' in the 1970s, to accept his Oscar.