The Creepy Creature of Vulture's Claw - S3-E10
Other mistake: The whole time Professor Greer's the Mantis he's around seven feet tall. When he's unmasked he's suddenly his own size again.
The Scooby Doo Show (1976)
1 other mistake in season 3
Starring: Frank Welker, Don Messick, Casey Kasem, John Stephenson
Continuity mistake: In the episode of Scooby movies where they meet the Three Stooges, Fred says that Velma is missing and they need to find her. When they go off to look for her they pass a window. Fred first, Daphne, then Velma (despite her being the one missing!), Shaggy, then Scooby.
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