Mr. McDabble is a teacher at Central High.
Mr. McDabble is a middle-aged Caucasian male with balding gray hair and thin glasses with circular lenses. He wears a blue suit with a gray shirt underneath and a red tie.
He is rather serious and somewhat grumpy. His reaction to meeting Shaggy Rogers again implies that he wasn't a good student and that he doesn't have fond memories of teaching him.
He taught Daphne Blake and Shaggy Rogers when they attended Central High.
The New Scooby and Scrappy Doo Show
McDabble was a victim of the clown, but also a suspect of taking the ruby himself because he wanted to close the carnival early, and because the box he had was believed to had contained the ruby inside. It was actually just the prize for the raffle, a watch he didn't want to get wet while he played target for the carnival dunk tank. The ruby was in his pocket.
- For no apparent reason, Mr. McDabble gives a sinister laugh when picking up the ruby. This appears to be simply for the audience to have a suspect.