In Last Laugh, the Circus Freak Trio worked together in the guise of being freak show performers in Zombozo's circus. As his minions, they would perform to lure in an audience for Zombozo. While Zombozo would feed on the crowd's laughter in his show, they would go out and strip the town of all its valuables. After Zombozo was beaten by Ben, the Circus Freak Trio set out on their own.
In Ghostfreaked Out, the Circus Freak Trio appeared trying to steal some trophies, but were ruthlessly thwarted by Zs'Skayr. While they were hiding, Zs'Skayr found them and forcibly became their leader, possessing the three of them to protect himself from a Sun Gun. A little after Zs'Skayr was fried, the Circus Freak Trio were taken to jail.
In Something Zombozo This Way Comes, the Circus Freak Trio have been rehired by Zombozo to distract Ben while he is feeding off everyone's fear. In the end Acid Breath helps Zombozo escape through a cannon and the Circus Freaks are taken to prison by the Plumbers.
Without a higher rank to command them, Acid Breath acts as the trio's leader.
Frightwig is second in charge and uses her elastic hair as her weapon.
Thumbskull is very strong with a thumb nail on the top of his head and on his hands. He plays as the muscle of the trio.
- Last Laugh (first appearance)
- Ghostfreaked Out
- Ben 10 vs. the Negative 10: Part 1
- Ben 10 vs. the Negative 10: Part 2
Ben 10: Omniverse
- Something Zombozo This Way Comes (first re-appearance)