It is a story book. Relates the experiences of a faithful messenger boy in a large city, who, in answering a call was the means of ferreting out a band of criminals who for years had baffled the police and detectives. The story tells of the many dangers and hardships these boys have to undergo; the important services they often render by their clever movements; and how by his fidelity to duty, Messenger Boy No. 48 rose to a most important position of trust and honor. It teaches boys that self-reliance, pluck, and the faithful performance of duties are the real secret of success.