In 1897, a horse-loving orphan named George McDill is banished from his first foster home in New York and sent by train to a small mining town west of Denver. The assigned family fails to meet him, so the town drunk takes him home. Nicknamed Mac on the train, his adventures include a strange woman hiding a mysterious box in his bag, a train robber who follows him to Colorado, a gold mining excursion where he is confronted by a mountain lion and a court proceeding that will secure his future. Mac learns about the unusual history of Glenwood Springs while working for the local horse trainer and...