The Hardy Boys are back in another thrilling mystery! In The Secret of the Old Mill, Frank and Joe Hardy find themselves in the middle of a dangerous counterfeit money scheme that leads straight to an abandoned mill with a sinister reputation. What begins as a simple exchange of a five-dollar bill at the Bayport station quickly spirals into a high-stakes investigation filled with suspense, deception, and surprising twists. With their signature courage and quick thinking, the Hardy brothers must unravel the secrets hidden within the old mill before it's too late. Packed with action, clever detective work, and heart-pounding moments, this classic tale keeps listeners guessing until the very end.