Matthew Lillard

as Shaggy Rogers (voice)

Frank Welker

as Scooby-Doo / Fred Jones / Monster (voice)

Grey DeLisle

as Daphne Blake (voice)

Kate Micucci

as Velma Dinkley / Sandi (voice)

Jason Isaacs

as King Arthur Pendragon (voice)

Nick Frost

as Merlin (voice)

Greg Ellis

as Herald / Herman Ellinger / British Passenger (voice)

Spike Brandt

as Mr. HB (voice)

Ted Barton

as Mayor Saunders / Sir Lancelot (voice)

Stephen Stanton

as Peanut Vendor (voice)

Kari Wahlgren

as Female Peasent (voice)

Fred Tatasciore

as Black Knight (voice)

Trevor Devall

as Man Cat (voice)