Doug, a tough city orphan, is rescued from the life of the streets by an uncle who takes him to his ranch in Colorado. Here, Doug must not only adjust to the healthy but baffling life of the country, but he must win over his reluctant cousin Jim, who resents the intrusion of a stranger. The boys make their truce and combine efforts to track down the criminal who has been undermining the ranch for mysterious motives. They find the culprit and through him save the ranch from financial collapse, discovering that their land contains rich deposits of uranium. Boys will enjoy the skillful combination of outdoor adventure, mystery and human interest with which this book abounds.