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)

John Stephenson
The Sheriff (voice)

Dee Bradley Baker
Sherman (voice)

Olivia Hack
Treena (voice)

Dave Attell
GPS (voice)