Before Downey signed on to play Tony Stark and secured his path to becoming the world's most bankable action star, he was by his own admission
an unreliable actor and a box office failure. Not even 10 years ago, who would have pegged the fringe Brat Packer and Chaplin
Oscar nominee to lead the charge on a series of Marvel franchises (just one film of which, The Avengers
, personally earned him $50 million) that show no signs of slowing down? Nobody, we're guessing. And yet that's what Iron Man did for Downey, making him professionally unbeatable just like Stark's alter ego.