Jimmy Neutron (voice)
Timmy / School Girl (voice)
Carl / Anti-Fairy Walla (voice)
Sheen / Anti-Fairy Walla (voice) (as Jeff Garcia)
Cindy (voice)
Libby (voice)
Special Vocal Effects / Goddard (voice)
Wanda / Mom / Anti-Wanda / Anti-Fairy #1 (voice)
Cosmo / Dad / Jorgen / Anti-Cosmo (voice)
Mr. Crocker (voice)
Binky (voice) (as Dee Baker)
A.J. (voice) (as Gary LeRoi Gray II)
Chet Ubetcha / Anti-Fairy #2 (voice)
Dr. Moist (voice)
Morgan Freeman / Anti-Fairy Walla (voice)
Professor Calamitous (voice)
Judy Neutron (voice)
Vicky (voice) (as Grey DeLisle)
Anti Fairies / Additional Voices (voice)
Chip Skylark (voice) (archive sound) (uncredited)