Discover
J.D. Daniels
Arnold (voice)

Francesca Marie Smith
Helga (voice)

Justin Shenkarow
Harold (voice)

Jamil Walker Smith
Gerald (voice)

Craig Bartlett
Brainy (voice)

Dan Castellaneta
Grandpa (voice)

Tress MacNeille
Grandma (voice)
Directing

Craig Bartlett
Director
Writing

Craig Bartlett
Writer

Craig Bartlett
Storyboard
Joe Ansolabehere
Writer
Steve Viksten
Writer

Tuck Tucker
Storyboard