James Isaac 'Jimmy' Neutron (voice)

Jet Fusion (voice)

Beautiful Gorgeous (voice)

Commander Baker (voice)

Professor Calamitous (voice)

Professor Crank (voice)

Goddard (voice)

Carl Wheezer / Monk / Voice / Clam (voice)

Judy Neutron / Ms. Jingle Bells / Female Monk (voice)

Hugh Neutron (voice)

Sheen Estevez (voice)

Ms. Fowl (voice)

Cindy Vortex / Tina Sue (voice)

Libby Fallfax / Ike (voice)

Betty Quinlan (voice)

Narrator / Head Monk

Chief (voice)