After helping WWE solve the mystery of the ghost bear in ''Scooby-Doo! WrestleMania Mystery'', the Mystery Inc. gang is seen at WWE's latest venture, The Muscle Moto X Off Road Challenge, an off-road racecar race for WWE superstars, with a big cash prize. Scooby-Doo (character) and Shaggy Rogers are there working at a food truck. Many WWE superstars are in the race, including WWE chairman Mr. Vince McMahon's own daughter Stephanie McMahon and her husband Triple H. Scooby and Shaggy are excited to hear that The Undertaker is going to be in the race.