Match wits with the amateur sleuths of the teen mystery series The Hardy Boys! Readers of all ages will enjoy the classic first book from 1927,  The Tower Treasure . Brothers Frank and Joe Hardy investigate the murmurs of a dying man who claims to have “secreted” his loot in the dilapidated towers of a mansion. Written by a group of ghostwriters under the name Franklin W. Dixon, the popular series has sold more than seventy million copies.