Frank Welker

Scooby-Doo / Fred Jones (voice)

Matthew Lillard

Shaggy Rogers (voice)

Mindy Cohn

Velma Dinkley (voice)

Grey DeLisle

Daphne Blake (voice)

Danica McKellar

Madelyn Dinkley (voice)

James Patrick Stuart

Whirlen Merlin (voice)

Crystal Scales

Crystal (voice)

Brian Posehn

Marlon Whirlen (voice)

Jeffrey Tambor

Mr. Calvin Curdles (voice)

Diane Delano

Mrs. Alma Rumblebuns (voice)

John DiMaggio

Groundskeeper Amos (voice)

Melique Berger

Upset Mother (voice)