The Great Gazoo is a tiny, green, floating alien who was exiled to Earth from his home planet Zetox as punishment for having invented a doomsday machine, a weapon of immense destructive power. His invention was a button which if pressed would destroy the universe in an explosive "ZAM," though he insists he made it on a whim ("I wanted to be the first on my block to have one.") with no intent of using it. Gazoo was discovered by Fred and Barney when his flying saucer crashed. Gazoo recognizes Fred and Barney's world as prehistoric Earth, implying Zetox banished him through time as well as space.