In Pixar’s Cars 3, Doc Hudson was Lightning McQueen’s mentor and crew chief.
Doc is introduced in Cars as the judge of Radiator Springs, but the first film later reveals that he was once the famous Fabulous Hudson Hornet. He won three Piston Cups before a crash ended his racing career and left him bitter about being forgotten by the racing world.
In Cars 3, Lightning studies Doc’s old racing methods after struggling against Jackson Storm. The film expands Doc’s history through flashbacks and conversations with Smokey, who knew him during his post-racing years. Doc’s experience teaches Lightning that successful racing depends on more than raw speed.
Doc died before the events of Cars 3, but his influence remains central. His number 51, workshop, and racing photographs connect Lightning’s present challenge with an earlier generation of competition. The mentor relationship also motivates Lightning to help Cruz discover her own ability.