Great good guy who didn't mind being a baddie
James Whitmore was great at playing wise and warm avuncular figures. I usually associate him with being on the right side of things.
But he didn't mind playing a baddie. There are at least two Gunsmokes where (1) he plays a white man in the white slave trade, and (2) a lawman who develops a love/hate fixation on a woman he's afraid is a painted lady. He torments the poor woman.
And usually he's the most pleasant person on the screen. Think Shawshank.