as Pierre Potkin

as Claude Horton

as Aloysius C. Whittaker

as Dr. Philip 'Painless' Pennington

as Roscoe Horne

as Newton

as Elmer Dugan

as Bob

as Dr. Dudley

as Himself

as Hercules Grub

as Alexander

as Self

as Self

as Spider Robbins

as Self

as Slick Foster

as Julius Swift

as Eggbert G. Higginbothom

as Julius Caesar

as Dr. J. Dockweiler Droop

as Zander Ulysses Parkhurst

as Robert Woolsey

as Addington Ganzy

as Gilbert Simpson

as Ginger Dandy

as Prof. Cunningham

as Himself / host

as Ned Lovett