Dr. Seuss/Igor

The Cat In The Hat as Igo

Norval the Fish as Dr. Holzuwurm

Joey as King Malbert

Sarah Hall-Small as Eva

Mack the Turtle as Brain

Sam-I-Am as Scramper

Mr. Brown as Dr. Glickenstein

The White Tufted Bird as Blind Woman/Killseum Fan 1

Vlad Vladikoff as Blind Orphan 1

Flying Dutchman (from Spongebob Squarepants) as Dr. Schadenfreude

The Lorax as Dr. Holzuwurm's Igor

Sylvester McMonkey McBean as Announcer/Royal Guard 2

Jane Kangaroo as Jaclyn/Heidi

Horton the Elephant as Dr. Herzschlag

Little Cat Fleep as Sonic (Cameo)

Morton the Elephant Bird as Tails (cameo)