The secret of the old mill

"The Secret of the Old Mill" by Franklin W. Dixon is an early 20th-century mystery that follows teenage brothers Frank and Joe Hardy as they turn detective to solve a perplexing case linked to a newly reopened old mill; an unexpected encounter with a counterfeit bill while waiting for their father begins their journey, plunging them into a world of suspicious characters and dangerous situations, as they discover a counterfeit scheme while interacting with the townsfolk which challenges the brothers, promising adventure and excitement, as they uncover what nefarious activities are happening.