In Pixar’s Cars 2, Mater serves as Lightning McQueen’s pit crew chief.
Lightning competes in the World Grand Prix, while Mater becomes involved in an international espionage story. Although Mater is usually portrayed as a rusty tow truck with limited sophistication, his accidental role in the race team places him directly beside Lightning during the competition.
Mater’s unconventional decisions create comic problems, but the film also uses them to drive the plot. His behavior is misinterpreted by British spies and criminals, which causes him to be treated as a secret agent. The pit-crew role therefore connects the racing storyline with the spy storyline.
Guido is Lightning’s tire-changing assistant, while Luigi operates the team’s tire-service operation. Finn McMissile is a British spy, not a member of Lightning’s racing crew. These roles can be confused because all four characters participate in the film’s international action.