Elroy is looking forward to the evening when his parents will hear about the high grades he’s gotten in school. But underachieving classmate Kenny Countdown switches report tapes on him, leaving George angry with his son after accidentally hearing the wrong one. Fearing his father’s wrath, Elroy runs away from home with Astro. Along the way, he encounters criminal Mugsy Megaton and his gang, which includes a gorilla for extra muscle. Mugsy tricks Elroy into breaking into a jewelry shop, then takes him back home so they can hide out from the police. After the mob captures George and Jane as well, it’s up to Astro to break free and get the police back to help save the family.