In the late 1950s, Disney contracted with the Stratemeyer Syndicate and Grosset & Dunlap to produce two Hardy Boys TV serials, starring Tim Considine and Tommy Kirk. The first of the serials, The Mystery of the Applegate Treasure, was aired on The Mickey Mouse Club in 1956 during the show's second season. To appeal to the show's audience, the Hardy Boys were portrayed as younger than in the books, seeming to be twelve or thirteen years old (Considine was 15 and Kirk was 14 during filming). The script, written by Jackson Gillis, was based on the first Hardy Boys book, The Tower Treasure, and the serial was aired in 19 episodes of fifteen minutes each with production costs of $5,700. A second serial, The Mystery of Ghost Farm, followed in 1957, with an original story by Jackson Gillis. This serial shares some elements with "The House on the Cliff", the second Hardy Boys book. However, for unknown reasons, no more serials were produced.