The Great Gazoo is a Zetoxian, a species of small green humanoid aliens, who was exiled to Earth in prehistoric times and made friends with the local "cavemen", or primitive Humans.
Gazoo was banished from his homeworld of Zetox as a punishment for creating a doomsday device, so powerful that it could possibly destroy the universe. Gazoo claims that he never intended using it, although he jokingly states that "I was the first one on my block to have one." Gazoo is only seen by his cavemen friends Fred and Barney, and their young children Pebbles and Bam-Bam. The other characters are apparently unable to see him because they don't believe in his existence.
Gazoo can do magic and float in mid-air.
- Outside of The Flintstones, Gazoo has made cameo appearances in the Duck Dodgers and The Simpsons, though in the latter he is portrayed as a separate entity called Ozmodiar.
- The Omnitrix from the Ben 10 franchise (or at least a replica designed by Black Hat Organization) contains DNA of Gazoo's species.