The gang visits a Science Expo in Houston, Texas, only to find that another mystery is waiting for them. It seems that a giant robot dog named Mecha Mutt has come to life, and legend has it that the Science Expo is haunted by a "Space Specter." The gang, along with their new friend Melanie Staples, investigates the mystery of the Mecha Mutt Menace and tries to stop the robot canine before he strikes again!