Charley is twelve the year after his brother, Johnny, is killed in the Battle of Gettysburg. Charley is a member of the Bowery Boys, a street gang in New York City, and believes he is brave and tough. Charley's sister, Noreen, is about to marry a man Charley hates. When he overhears Noreen agree that Charley will be sent to a school for incorrigible boys if he doesn't behave, Charley feels betrayed and runs away with a Yankee military regiment. Because Charley believes he is brave in the street situations where he is most at home, he believes he'll prove himself brave on the battlefield. But when the bullets begin to fly and Charley has an up-close view of battles and death, he is frightened. When a bullet strikes his drum, he breaks and runs away.