The Man from G.R.A.M.P.A.

Dan Castellaneta

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

Julie Kavner

Marge Simpson / Patty Bouvier / Selma Bouvier (voice)

Nancy Cartwright

Bart Simpson / Nelson Muntz / Ralph Wiggum (voice)

Yeardley Smith

Lisa Simpson (voice)

Hank Azaria

Moe Szyslak / Chief Wiggum / Apu / Comic Book Guy / Carl (voice)

Harry Shearer

Ned Flanders / Mr. Burns / Smithers / Skinner / Lenny (voice)

Maurice LaMarche

Orson Welles (voice)

Stephen Fry

Terrance / Hazel / MI5 Man (voice)

Alex Désert

Carl Carlson (voice)

Pamela Hayden

Retirement Center Lady (voice)

Tress MacNeille

Olive (voice)

Robin Atkin Downes

MI5 Agents (voice)

Chris Edgerly

Out-of-Breath Old Man (voice)

Brian George

MI5 Agents (voice)

Dima Malanitchev

Russian See 'n Say (voice)

Kevin Michael Richardson

MI5 Agents (voice)