Meldar Prime (voice)
April (voice)
James Isaac 'Jimmy' Neutron / Alien Actress / Alien Woman (voice)
Hugh Neutron / General Abercrombie (voice)
Judy Neutron / Mrs. Vortex (voice)
Carl Wheezer / Mr. Wheezer / Mrs. Wheezer / Test Pilot / Announcer (voice)
Sheen Juarerra Estevez / Army Guard (voice)
Cindy Vortex (voice)
Libby Folfax (voice)
Miss Fowl (voice)
Sam / Corky Shumatsu (voice)
Gorlock #1 / Brain #2 / Mayor Quadar (voice)
Gorlock #2 / Brain #1 (voice)
Bolbi Stroganofsky / British Tourist (voice)
Vendanna (voice) (as Grey DeLisle)
Sir. Estevez (voice)
Meldar (voice)
Goddard (voice)