In this feature film based on the "Flintstones" TV show, operative Rock Slag is injured during a chase in Bedrock. Slag's chief makes a decision to change the injured Slag with Fred Flintstone, that just takes place to look like him. The journey takes Fred to Paris and also Rome, which benefits Wilma, Barney, as well as Betty, but can Fred aluminum foil the mysterious Green Goose's wicked plan for a destructive missile without letting his other half and pals in on his secret?