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.
| Episode number | Episode title | Air date | |
|---|---|---|---|
| 0 | An Introduction | Oct 1, 1956 | |
| 1 | A Stranger | Oct 2, 1956 | |
| 2 | A Real Case | Oct 3, 1956 | |
| 3 | The First Clue | Oct 4, 1956 | |
| 4 | The Fugitive | Oct 5, 1956 | |
| 5 | Applegate's Gold | Oct 8, 1956 | |
| 6 | Dig for Treasure | Oct 9, 1956 | |
| 7 | A Pirate's Chest | Oct 10, 1956 | |
| 8 | Boys in Trouble | Oct 11, 1956 | |
| 9 | Female Detective | Oct 12, 1956 | |
| 10 | Iola's Bravery | Oct 15, 1956 | |
| 11 | Footsteps in the Tower | Oct 16, 1956 | |
| 12 | The Prisoner Speaks | Oct 17, 1956 | |
| 13 | The Strange Confession | Oct 18, 1956 | |
| 14 | A Golden Clue | Oct 19, 1956 | |
| 15 | The Final Search | Oct 22, 1956 | |
| 16 | The Tower's Secret | Oct 23, 1956 | |
| 17 | Never Say Die | Oct 24, 1956 | |
| 18 | Boys in Danger | Oct 25, 1956 | |
| 19 | The Tower Treasure | Oct 26, 1956 |
| Episode number | Episode title | Air date |
|---|---|---|
| 0 | An Introduction | Sept 13, 1957 |
| 1 | Beginning of the Puzzle | Sept 20, 1957 |
| 2 | Detective Joe | Sept 27, 1957 |
| 3 | Who Feeds the Cat? | Oct 4, 1957 |
| 4 | Two Private Eyes | Oct 11, 1957 |
| 5 | Man Named Fred | Oct 18, 1957 |
| 6 | Animals in Danger | Oct 25, 1957 |
| 7 | Catching a Ghost | Nov 1, 1957 |
| 8 | The Ghost Speaks | Nov 8, 1957 |
| 9 | Lacey's Wonderful Will | Nov 15, 1957 |
| 10 | Detectives in Trouble | Nov 22, 1957 |
| 11 | The Ghost Confesses | Nov 29, 1957 |
| 12 | Iola to the Rescue | Dec 6, 1957 |
| 13 | Panic at the Zoo | Dec 13, 1957 |
| 14 | Uncle Billy's Secret | Dec 20, 1957 |
The theme song was performed by Thurl Ravenscroft and played over clips from Disney's Treasure Island.
In December 2006, the Disney studio issued a Treasures DVD for The Hardy Boys: Mystery of the Applegate Treasure.