Cheyenne, a wealthy former rock star (Penn), now bored and jaded in his retirement embarks on a quest to find his father's persecutor, an ex-Nazi war criminal now hiding out in the U.S. Learning his father is close to death, he travels to New York in the hope of being reconciled with him during his final hours, only to arrive too late. Having been estranged for over 30 years, it is only now in death that he learns the true extent of his father's humiliation in Auschwitz at the hands of former SS Officer Aloise Muller - an event he is determined to avenge. So begins a life-altering journey across the heartland of America to track down and confront his father's nemesis. As his quest unfolds, Cheyenne is reawakened by the people he encounters and his journey is transformed into one of reconciliation and self discovery.