Timmy Turner

Tara Strong

James Isaac Neutron

Debi Derryberry

Goddard

Frank Welker

Sheen Estevez (voice)

Jeffrey Garcia

Cindy Vortex (voice) / Cindy Vortex / Tina Sue (voice)

Carolyn Lawrence

Carlton Ulysses Wheezer

Rob Paulsen

Nick Dean (voice) / Britney (voice) / Nick Dean

Candi Milo

Hugh Neutron (voice) / Hugh Neutron / General

Mark DeCarlo

Judy Neutron (voice) / Judy Neutron / Woman (voice)

Megan Cavanagh

Libby Folfax (voice) / Libby Folfax / Chuck (voice)

Crystal Scales

Ms. Fowl (voice) / Ms. Fowl / Lady (voice)

Andrea Martin

Sam Melnick (voice) / Corky Shimatzu / Larry Llama (voice)

Billy West

Wanda

Suzanne Blakeslee

Bolbi (voice) / Bolbi / Pitz

Phil LaMarr

Cosmo/Mr. Turner/Jorgen von Strangle

Daran Norris

Ultra Lord (voice) / Popbot / Gortox

Jim Cummings

Vicky/Principal Waxelplex

Grey Griffin

Nanobot #2 (voice) / Max / Wilderman

Tom Kenny

Travoltron / Barbarino (voice) / Newscaster

Jeff Bennett

Mr. Denzel Crocker

Carlos Alazraqui

Dr. Dark / Pizza Monster (voice) / Head Monk (voice)

Corey Burton

Sanjay/Elmer/Fairy Agent No. 1

Dee Bradley Baker

Zix / Ticket Taker (voice) / Tee

Maurice LaMarche

AJ Ibrahim

Gary Leroi Gray

Betty Quinlan (voice)

Kath Soucie

Francis

Faith Abrahams

Tour Guide

Jim Ward

Professor Calamitous (voice)

Tim Curry

Chester McBadbat

Jason Marsden

Goddard Evil Robot Voice

Dan Castellaneta