Cast[]
- Oscar as Horton
- Henry as The Mayor of Whoville
- Summer as Sally
- Cobby as Jojo
- Denzel as Morton
- Gertie as Katie
- Estelle as Mrs. Quilligan
- Meg as Jessica
- Mimi Monstermouth as Kangaroo
- Milo as Rudy
- Roberto as Tommy
- Mr. Growl as The King Monkey
- Mini-Monsters as Monkeys
- Roddy as Vlad
- Roarsettes 1&2 as Hedy and Hooly
- Izzy as Helen