Chester McGill is a former extreme athlete residing in New Zealand, Chairman of the Waikikamukau race, and the main antagonist of Rocket Power: Race Across New Zealand. He's obsessed with having his son Theodore McGill follow in his footsteps by winning the Prince Waikikamukau competition by any means necessary.
In the first Prince Waikikamukau competition, Raymundo competed against Chester and Ray was on the verge of winning the final event of the competition which was a down hill skiing race. But just as Ray was about to win, Chester suddenly appeared in front of Ray at the finish line and won 1st place. Ray is bitter about the loss years later and believes (correctly) that Chester must have cheated during that race.
Chester’s son Theodore McGill is competing in the current Waikikamukau competition and Chester expects him to win like he did. But after losing the first race, Chester angrily admonishes Theodore and tells him that McGills have always done whatever it takes to win.
Chester than began to sabotage the Rockets’ equipment during the night so that Theodore could win. He began by tampering with the axle in Otto’s skateboard and stole the replacement axles. This caused Otto to wipeout in the second race while Theodore tied with Reggie for 1st place. Chester than stole the Rockets’ map for the windsurfing race and replaced it with a map that incorrectly identified the location of a sandbar. Otto ended up crashing into the sandbar and Reggie quit the race in anger over her father being solely focused on Otto which let Theodore win.
Before the final snowboarding race began, Chester told Theodore to cut through the woods as an illegal shortcut. When Theodore expresses dismay at the idea, Chester than reveals to Theodore that he was responsible for sabotaging Otto and his team in order for Theodore to win. During the race, Theodore reluctantly takes the shortcut and almost wins, but Reggie manages to catch up with him in time and they tie for 1st place again.
After the race is over, Theodore is crowned the new Prince Waikikamukau by his father. But Theodore can’t handle the guilt and confesses that he cheated in the final race. After seeing Theodore confess, Chester loses his composure and lets slip that he took the same shortcut in the first Waikikamukau competition with everyone overhearing him and Ray is vindicated. Theodore is disqualified and Otto and Reggie tie for Prince and Princess Waikikamukau. Chester ends up having his Prince Waikikamukau medal from the first games revoked and it’s given to Ray.