In Pixar's Cars, the retired racer revealed to be Radiator Springs' doctor is Doc Hudson.
Doc initially presents himself as the town's local physician, but the story later reveals that he was once the famous Hudson Hornet. He won three Piston Cups before a crash ended his racing career.
Doc's experience makes him an important mentor for Lightning McQueen. He teaches McQueen that racing skill includes more than speed, including control, judgment, and respect for others.
The character is voiced by Paul Newman, whose connection to racing helped give Doc unusual authenticity. The Hudson Hornet was also a real automobile associated with early NASCAR success, although Doc himself is a fictional character.