The Phantom Funnyman

The Phantom Funnyman is a story in Scooby-Doo... Mystery Comics #23

Premise
On Mike Moore's television show, a self-proclaimed phony ghost challenges the gang to unmask him -- with ten thousand dollars for charity at stake as the prize if they do. Scooby and the gang hurry to the haunted house, but once inside, they begin to vanish one-by-one.

Characters

 * Scooby-Doo
 * Shaggy Rogers
 * Fred Jones
 * Daphne Blake
 * Velma Dinkley
 * Mike Moore