Scooby-Doo, Where are You? made its CBS network debut on Saturday, September 13, 1969 with its first episode, What a Night for a Knight. The original voice cast featured Don Messick as Scooby-Doo, Casey Kasem as Shaggy, Frank Welker as Fred, Nicole Jaffe as Velma, and Stefanianna Christopherson as Daphne.