Nat Faxon

as Captain Underpants / Mr. Krupp (voice)

Jay Gragnani

as Harold (voice)

Ramone Hamilton

as George (voice)

Sean Astin

as Narrator (voice)

Dayci Brookshire

as Jessica / Dressy (voice)

Jim Cummings

as Santa (voice)

Jorge Diaz

as Melvin / Stanley Peet (voice)

Peter Hastings

as Comic Narrator (voice)

Evan Kishiyama

as Steve 'Gooch' Yamaguchi (voice)

Kevin Peaty

Director

Erik Kling

Director