In the early 1850s, twelve-year-old Peter Blair's mother has died and his father has gone to Santa Fe to seek his fortune. Left in St. Louis, a friend has agreed to care for Peter. Before long his father's acquaintance "Uncle" Seth goes back to St. Louis to check on Peter. But Peter is lonely and persuades his new uncle to take him to Santa Fe to be with his father. On the way, Uncle Seth leads their wagon train through an Indian attack, desertion by greenhorns, a buffalo stampede, a violent storm, and many other hardships. When Peter finally reaches his destination, he finds that his father is no longer in Santa Fe. Now he must go on yet another journey-one that almost proves fatal.