Nathan Lane

Spot Helperman / Scott Leadready II / Scott Manly-Manning (voice)

Kelsey Grammer

Dr. Ivan Krank (voice)

Shaun Fleming

Leonard Amadeus Helperman (voice)

Debra Jo Rupp

Mrs. Mary Lou Moira Angela Darling Helperman (voice)

David Ogden Stiers

Mr. Jolly (voice)

Jerry Stiller

Pretty Boy (voice)

Paul Reubens

Dennis (voice)

Megan Mullally

Adele (voice)

Wallace Shawn

Principal Crosby Strickler (voice)

Rob Paulsen

Ian Wazselewski (voice)

Jay Thomas

Barry Anger (voice)

Estelle Harris

Mrs. Boogin (voice)

Genie Francis

Marsha / Marcia (voice)

Anthony Geary

John / Juan (voice)

Rosalyn Landor

The Blue Fairy (voice)

David Maples

Beefeater (voice)

Pamela Adlon

Trevor / Taylor / Tyler (voice)

Timothy Stack

Father (voice)

Emma Steinkellner

Little Girl (voice)

Ken Swofford

Officer White (voice)

Lauren Tom

Younghee (voice)

Mae Whitman

Leslie Dunkling (voice)

Kevin Michael Richardson

Conductor (voice)