Frank Welker
Scooby-Doo / Fred Jones / Self
Matthew Lillard
Norville 'Shaggy' Rogers / Self - Voice of "Shaggy"
Grey DeLisle
Daphne Blake / Self - Voice of "Daphne"
Kate Micucci
Velma Dinkley / Self - Voice of "Velma"
Janel Parrish
Janel Parrish - Host
Jerry Beck
Self - Animation Historian and Author
David Silverman
Self - Director and Producer, "The Simpsons"
Seth Green
Self - Actor, "Scooby-Doo 2: Monsters Unleashed"
Tony Cervone
Self - Director, "Scoob!" / Showrunner, "Mystery Incorporated"
Tom Sito
Self - Animator, Historian
Joseph Barbera
Self - Hanna-Barbera Co-Founder (archive footage)
Mary Lynn Rajskub
Producer Bryn
Baron Vaughn
Bram Penobscot - Scooby's Vocal Coach
Casey Kasem
Shaggy Rogers (voice) (archive footage)
Diedrich Bader
Batman - Concerned Citizen (voice)
'Weird Al' Yankovic
Self - Singer, Songwriter, Accordionist
Olivia Liang
Olivia Liang - Shaggy's Martial Arts Trainer
Karamo Brown
Costume Designer Carter
Mitch Watson
Self - Showrunner, "Mystery Incorporated"
Cheri Oteri
Lazlo the Mechanic
Brendan Jennings
Arlo Davidsonman - Team Scooby
Vadym Krasnenko
Snow Ghost
Lindsey Alena
Additional Voices (voice)
Dominic Catrambone
Additional Voices (voice)
Fred Tatasciore
Additional Voices (voice)