Calvin, played by Sam Elliott (A Star is Born, The Big Lebowski), seems to be just an ordinary old man with a dog. When Aidan Turner (The Hobbit, And Then There Were None) plays him as a young man, it turns out that he was the one who killed Adolf Hitler. Decades later, Calvin has become a hermit, but the U.S. government comes to him again, hoping that he can save the world again: go to Canada and cross mountains and kill the legendary "snowman" Bigfoot, who carries a deadly plague.