In A Boy's Fortune, Ben Baker, 16, leaves his widowed mother in Connecticut, to seek his fortune in New York City. He goes to New York and takes a job working in his rich uncle's department store, unaware that his uncle made his fortune by robbing Ben's late father. Five years earlier, Ben's father received an inheritance in bonds, then died suddenly while visiting his brother-in-law, Nicholas Walton. When he arrives in New York, Ben calls on his Uncle Walton, who rebuffs him. Ben is offered job as a personal secretary if he will take the name "Philip Grafton" because he bears a strong resemblance to a real Philip Grafton, who had died. The real Philip's guardian, Major Richard Grafton, fraudulently continues to receive a stipend as Phillip's guardian. The Major then "adopts" Ben to replace the deceased Philip. To perpetuate the fraud, the Major takes Ben to Europe. When the scheme is about to be exposed, the Major has Ben committed to an insane asylum in Switzerland. Ben must escape to uncover the theft before it is too late.