"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...