Ten years before Custer’s Last Stand in the Big Horn Mountains of Montana, Sioux and Cheyenne Indians led Captain Fetterman and 80 troopers into a trap and massacred all in the Wyoming-Dakota Territory. What followed was a fort under siege on the first day of the worst snow storm of the century, where temperatures dropped to 40-below zero; and two civilian workers volunteered to ride horseback more than 250 miles for help in one of the most unbelievable survival stories in western history. Based on a true story. As a movie, this would be a cross between The Revenant and Man in the Wilderness.