The Secret of the Old Mill #3By: Franklin W. Dixon The Hardy Boys series, first published in 1927, has sold more than 70 million copies! Now with a brand new look, this is an edition that collectors won't want to miss! In The Secret of the Old Mill, the third book in the incredibly popular, long running series, Frank and Joe Hardy are on the case to bust a counterfeit money ring. A special treat for Hardy Boys fans and any reader who's new to the series.