Scooby and Shaggy travel into the desert to discover that Dr. Phineus Phibes has built a giant, weaponized robot in his image.  Phibes' plan is to merge with the robot through a "neural connection" and become one with it, thus making himself both all powerful and immortal. Scooby and Shaggy put a big kink in Phibes' plans by accidentally stowing away in the giant robot and ending up at the controls. After chasing Scooby and Shaggy across the desert to Hoover Dam, Phibes ejects them from his robot by overriding the controls and picking them out if its nose with a giant robot finger. When Phibes gets inside his giant robot, Scooby and Shaggy have no chance. That is until Scooby eats a Super Scooby Snack that makes him a giant robot as well. Scooby is victorious in the "bot-vs-bot" battle that follows, and Phibes is once again foiled.