The Secret of the Old MillThe Hardy Boys Series
Franklin W. Dixon
A thrilling tale of mystery and sleuthing, this book follows brothers Frank and Joe as they delve into the secrets of an old mill. The boys must use their wits to solve two perplexing cases: one involving counterfeiters and the other tied to national security. How will they escape from their dangerous predicament? Find out in this exciting read.
first published in 1927