In this novel, a teenage boy runs away from his unhappy Chicago home and rides a train headed for northern Michigan. While passing through a small town, the engine breaks down. An unusual series of circumstances determines he will remain indefinitely in that town. In the ups and downs that follow, he makes a life for himself meeting supportive friends and eventually working for the railroad.

The story develops the theme that railroads can be captivating whether they are actual (like the Chesapeake & Ohio or Illinois Central), scale models (like Lionel or American Flyer), or merely metaphorical (like the pre-Civil War Underground Railroad). All play a part in the plot presented here.