1. Daniel Day Lewis - Abraham Lincoln
To be fair, I probably could have included every last one of Daniel Day-Lewis's roles on this list. He has a reputation for doing everything in his power to transform himself into his characters, after all. Fun times were had by all during the filming of My Left Foot, when he refused to break character...which in this case involved a man who suffered so severely from cerebral palsy that he could only effectively move his left foot. But the role I want to focus on is the one that won him his third Leading Actor Oscar -- Abraham Lincoln. It's truly astonishing how he can manage the transition from Daniel Day-Lewis, handsome, Irish actor, into the man who, after being called two-faced, once quipped, "If I had two faces, would I be wearing this one?" An already brilliant performance is thus brought to new heights by his almost unsettling physical transformation.