Dan Castellaneta

Mr. Ramish

Zoo Keeper

Milt

Joe Spencer

Homer Simpson / Abe Simpson / Barney Gumble / Krusty (voice)

Patrick Senior

Homer Simpson (voice) / Homer Simpson / Abe Simpson / Barney Gumble / Krusty (voice)

Jenna / Judge Markway

Dr. Kinny

Frank Whitaker

Officer Novarro

Robot Devil (voice)

Dr. Stein

Derry Murbles

Agent Armstrong

Judge Needum Taylor

Kaznian Astronaut / Socialite / Photographer (voice) / Minister / Guard (voice)

Guard (voice) / Kobra Commando (voice)

Goon (voice) / Mr. Geminini (voice) / Private Cleoutus Dobbs / Baxter (voice)

Scarface (voice) / Wesker / Scarface (voice)

Steve Michaels

Dr. Milton Hastings

Professor (uncredited)

Ray Winters

Homer Simpson (voice)

(voice)

Mr. Jumba (voice)

Brad

Peter Oliver

Bryan

Animal Control Officer (voice) / Announcer (voice; uncredited) / Big Arnold (voice) / Bus Driver (voice) / Bus Driver / Grandpa's Grandfather (voice) / Buyer (voice) / Conductor (voice) / Delivery Man (voice) / Doctor Steiglitz / Grubby (voice) / Dr. Steiglitz (voice) / Earl (voice) / Engineer (voice) / Grandpa Phil (voice) / Grandpa Phil / Chicken Man (voice) / Grandpa Phil / Cop #1 (voice) / Grandpa Phil / Grandpa Phil's Father / Jolly Olly Man (voice) / Grandpa Phil / Judge (voice) / Grandpa Phil / Nick Vermicelli (voice) / Grandpa Phil / Nolo (voice) / Grandpa Phil / Reporter (voice) / Grandpa Phil's Father (voice) / Guard / Canned Speech (voice) / Ice Kentucky (voice) / Jolly Olly Man (voice) / Jolly Olly Man / Baseball Announcer (voice) / Jolly Olly Man / Fireman (voice) / Mover (voice) / Nick Vermicelli (voice) / Peter (voice) / Referee (voice) / Rico (voice)

Zabar (voice)

Genie (voice)

Dr. Harvat

Mr. Horner / Franklin the Frog (voice)

Dracula (voice)

David Champion / Homer Simpson

Dr. McNally

Emmett Brown (voice)

Lazaar (voice)

Dr. Zibaldo (voice) / Prince Wudolph (voice)

Megavolt (voice)

Mr. Thickly (voice)

Additional Voice Talent (voice) / Boney / Bureauocrates (voice) / Bureauocrates (voice) / Homer (voice) / Homer / Nectar guy (voice) / Ticket salesman (voice)

Dave Bishop (voice) / Mr. Bishop (voice)

Boris (voice) / Captain Howdy (voice) / Coluans (voice)

Stan

Walt

Earthworm Jim / Grim Reaper / Turns-His-Eyes-Inside-Out Boy / Evil Jim / Abraham Lincoln / Japius / Stock Broker

Dr. Harvey (voice)

Self

Sven Jorgensen

Stewart (voice)

Dunkirque (voice)

Alan Frakesh

Homer Simpson / Itchy / Barney / Abe Simpson / Stage Manager / K

Mr. Kenny

Male Fan

Carlson

Genie (voice)

Additional Voices (voice)

Homer Simpson / Grampa Simpson (voice)

Homer Simpson / Barney Gumble (voice)

Thing One / Thing Two (voice)

The Robot Devil (voice)

Man in Chair

Narrator (voice

Homer Simpson (voice)

Mr. Mysterio / Woodenleg Wally (voice)

Maitre D'

Homer Simpson (voice)

Homer Simpson / Barney Gumble (voice)

Guard #1 (voice)

Auctioneer / Horse Trader (voice) (uncredited)

Homer Simpson / Willie / Grampa Simpson/ Kodos/ Various (voice)

BoE Agent #2 (voice)

Priest (voice)

Iron Shoes / Priest (voice)

Homer Simpson

Brian

Tall Customs Dog / Angel Dog #1 (voice)

Jim Orr

Grandpa (voice)

Grandpa 'Steely' Phil / Nick Vermicelli (voice)

Gary

George Agrande

De Mille

Homer Simpson, Barney Gumble, Grampa Simpson (voice)

Homer (voice)

Aaron Spelling

Homer Simpson

Homer Simpson (voice)

Professor Crank (voice)

Partlow

The Postman (voice)

Homer Simpson (voice)

Stretch (voice)

Comet / Blitzen (voice)

Human Cannonball

Bumpkin

(9 episodes)

(1 episode)