In 1956, the Mickey Mouse Club did a serial version of the Hardy Boys “Tower Treasure” story. There are many differences from the book, the main one being that the boys are several years younger than in the book. But it captured my imagination as a young kid, and I have it on DVD.
“Gold doubloons and pieces of 8, all belonged to Applegate. The coast is clear but listen, wait”.... The only part of the song preceding the episodes of ?Hardy Boys mystery about some old man named Applegate. LOVED them, along with Spin and Marty.