Frank Welker as Scooby-Doo / Fred (voice)

Mindy Cohn as Velma (voice)

Grey DeLisle as Daphne (voice)

Matthew Lillard as Shaggy (voice)

Greg Ellis as Marcus Brancusi (voice)

Maurice LaMarche as Archambault (voice)

Peter Stormare as Wulfric von Rydingsvard (voice)

Jeff Dunham as Schmatko / Conductor (voice)

Carlos Ferro as Oliverio / Sisko (voice)

Jess Harnell as Human Scooby-Doo / Guard (voice)

Jim Meskimen as Phil Flaxman / Detective (voice)

Candi Milo as Jean (voice)

Hynden Walch as Lena / Joan (voice)

Craig Ferguson as Whitney Doubleday (voice)