Hopalong Cassidy is a fictional cowboy hero created in 1904 by the author Clarence E. Mulford, who wrote a series of short stories and novels based on the character. The success of the television series made Boyd a star. The Mutual Broadcasting System began broadcasting a radio version, with Andy Clyde (later George MacMichael on Walter Brennan's ABC sitcom The Real McCoys) as the sidekick (except for episodes 28 to 53 of the 105 episode series, when, for reasons unknown, he was replaced by several different radio actors). The show was syndicated from 1948 to 1950, then began broadcast on Mutual on January 1, 1950. At the end of September, the show moved to CBS Radio, where it ran until 1952.
