John, a young Navajo, is frightened to leave his lifelong home on the reservation and move to Minnesota with his mother and new stepfather. The boy’s grandfather assures him he’ll be all right since he has an “unbreakable code,” the Navajo language. The man goes on to tell the story of how he and other Navajos were recruited by the Marines and developed a message code based on their native language that helped the U.S. in the Pacific during World War II. — School Library Journal