The Ghost was the disguise of Gloria Gertrude.
Physical appearance[]
It's a classic ghost design, depicting of a white sheet with two black cutout circles for eyes.
Personality[]
It was a frightening individual who was also relentless and quite smart. As it chased Shaggy and Scooby, while being able to see through every single disguise they use in an attempt to trick him.
History[]
Scooby-Doo! Mystery Cases[]
Gloria unmasked.
The ghost made an unexpected appearance in the theater's backstage area where Shaggy and Scooby were when they were searching for Scooby's costume for the puppet show.
It went to attack the cowardly duo, but they tried multiple disguise tricks (consisting of pretending detectives. Trying to arrest the ghost while dressed up as police officers, blending in as two monsters, dressing up as hippies and finally pirates) in attempting on fooling it into leaving them alone, but it was persistent and wasn't fooled at all.
During their pirate disguise trick, it let out a roar which caused Shaggy to throw it away in fear which sent it flying across the room cutting a nearby rope, right before it was about to get the two, a bunch of sandbags fell from the ceiling and landed on the ghost trapping. It was then unmasked by Shaggy revealing it to be famous actress, Gloria Gertrude. She was jealous of not getting the lead role so she dressed up as a ghost to scare them away so she could get it for herself.