Debi Derryberry
Jimmy Neutron (voice)
Mark DeCarlo
Hugh Neutron (voice)
Megan Cavanagh
Judy / Vox 2000 (voice)
Rob Paulsen
Carl / Mr. Wheezer / Butch (voice)
Jeffrey Garcia
Sheen (voice) (as Jeff Garcia)
Carolyn Lawrence
Cindy Vortex (voice)
Crystal Scales
Libby (voice)
Andrea Martin
Ms. Fowl (voice)
Billy West
Sam / Louie (voice)
Candi Milo
Nick (voice)
Jeffrey M. Gunn
Nick's Singing Voice (as Jeff Gun)
Frank Welker
Goddard / Twonkies (voice)
Graystar
Themselves (voice)