Doc Hudson is the retired racer who becomes a judge in Pixar's Cars.
Doc lives in Radiator Springs and initially hides his earlier career from Lightning McQueen. He was the famous Hudson Hornet, a three-time Piston Cup champion whose racing career ended after a crash and a long recovery.
Paul Newman voiced Doc Hudson in Cars, making the role one of the actor's final major film performances. Newman had a long connection with motor racing, including professional competition, which gave the character's racing background an especially notable connection to his performer.
Doc's guarded attitude changes as he becomes Lightning's mentor. His history explains why he understands both the physical risks of racing and the emotional damage caused when a champion is suddenly pushed aside.