Nigel 'Numbuh 1' Uno / Hoagie Pennywhistle 'Numbuh 2' Gilligan Jr / Numbuh 101 (voice)
Ben Diskin
Kuki 'Numbuh 3' Sanban (voice)
Lauren Tom
Father (voice)
Maurice LaMarche
Patton 'Numbuh 60' Drilovsky (voice)
Matt Levin
Monty Uno (voice)
Frank Welker
Grandfather (voice)
Neil Ross
Count Spankulot (voice)
Daran Norris
Rachael T. 'Numbuh 362' McKenzie (voice)
Rachael MacFarlane
Sector Z Numbuh 0.1 - Bruce (voice)
Ogie Banks
Sonya - Number 83 / Lee - Numbuh 84 (voice)
Janice Kawaye
Numbuh Zero / Lenny - Sector Z Numbuh 0.4 (voice)
Dave Wittenberg
Additional Voices (voice)
Cam Clarke
Wally 'Numbuh 4' Beatles / Mr. Fibb / Toilenator / Joaquin / Tommy Gilligan (voice)
Dee Bradley Baker
Candi Milo
Abigail 'Numbuh 5' Lincoln / Former Numbuh 11 - Cree Lincoln (voice)
Cree Summer
Chad Dickson (voice)
Jason Harris
Crazy Old Cat Lady/Gramma Stuffum (voice)
Grey DeLisle
Mr. Boss / Mr. Fizz / Benedict Wigglestein (voice)
Jeff Bennett
Fanny 'Numbuh 86' Fulbright / Computer (voice)
Jennifer Hale
Stickybeard (voice)
Mark Hamill
Knightbrace / Mr. Wink (voice)
Tom Kenny
Story
Mo Willems
Writer
Director
Guy Moore
Animation Manager
Maurice Joyce
Tom Warburton
Creator
Alison Wilgus
Original Music Composer
Steve Rucker