In Pixar's Cars, the town's traffic judge and doctor is Doc Hudson.
Doc is an elderly blue 1951 Hudson Hornet who lives in Radiator Springs. He initially appears stern and private, but the story gradually reveals that he was once a celebrated race car known as the Fabulous Hudson Hornet.
His medical role is a playful extension of the film's vehicle-centered world: Doc treats cars rather than people, and he also serves as the town's judge. His past explains why he is skeptical of Lightning McQueen's fame and impatient with the younger racer's arrogance.
A common mix-up is identifying Doc by his racing nickname instead of his character name. The Fabulous Hudson Hornet is the title associated with his racing career, while Doc Hudson is the name used in Radiator Springs. The character is voiced by Paul Newman, whose performance was among the film's most notable voice roles.