Henry, Jessie, Violet and Benny are four orphaned brothers and sisters who mysteriously appear in a small town on a warm summer night. No one knows who these young wanderers are or where they have come from. Frightened to live with a grandfather they have never met, the children make a home for themselves in an old abandoned red boxcar they discover in the woods. Henry, the oldest, goes to town to earn money and buy food and supplies while the other kids make a home in the boxcar finding old dishes and scraps in a junkyard. Ambitious and resourceful, the plucky children make a happy life for themselves. As time passes, they discover the struggles and rewards of independence as well as the joys of family - until one day Violet gets too sick for her brothers and sister to care for her. They must take Violet to a doctor risking discovery and the loss of their secret home in the forest.