Luke Ransom was just eighteen years old when he answered an ad in a St. Louis newspaper that would change his life forever. The American Fur Company needed one-hundred enterprising men to travel up the Missouri River—the longest in North America—all the way to its source. They would hunt and trap furs for one, two, or three years. Along the way, they would face unimaginable hardships: grueling weather, wild animals, hunger, exhaustion, and hostile attacks by the Blackfeet and Arikara. Luke Ransom was one of the brave men chosen for the job—and one of the few to survive …