Continuity mistake: When the villain drops the wall flat on Shaggy, it drops with Shaggy going through the window as he stands, then hits the floor. The next shot the flat on the floor disappears, then reappears in the shot after that.
Continuity mistake: When Scooby dons the cloak and hat, there is a blank wall behind him. As he begins running, Shaggy is suddenly with Scooby and a shelf filled with boxes appears on the previously blank wall.
Continuity mistake: A wall flat behind Shaggy with an open window and a closed door is pushed by the villain to fall onto Shaggy, but door on the flat disappears and is now an open space in the wall flat.
Continuity mistake: Velma has her arms spread as she stands in front of the Scooby gang, but nobody is behind her in the next shot.
Continuity mistake: Velma counts off the clues on her fingers close to her face, but in the next shot her hands are at her side.
Continuity mistake: Velma is facing to her right as she holds the engraving plate, but the next shot she is facing left.
Continuity mistake: Shaggy's hands on the violin case change positions depending on whether the case is open or closed.
Continuity mistake: After the villain is caught, Scooby is in the theater rafters, but his spots are missing.
Continuity mistake: The background houses and fences repeat as Shaggy and Scooby carry their pizza home.
Continuity mistake: While Scooby and the gang speak with the doorman, Scooby's spots disappear.
