该片讲述了一个牧羊少年因目睹一起杀人案，竟被人推下悬崖。一个平民在孤独的抗议，被当街射杀，尸体在流血，无人问津。正直的警察局长蓬纳维亚早就对法律的公正丧失信心，雇凶不成，就自己充当杀手，干掉了这一切罪恶的幕后黑手——一个名义上的地产承包商罗蒙诺。而自己在自首后，被买通的犯人在狱中杀害。
杰西•詹姆斯（BradPitt布莱德•彼特饰），南北战争时期最著名的强盗，他与兄长组建的詹姆斯帮伙同其喽罗犯下无数宗抢劫案，即使防卫再出色的银行也难逃他们的魔掌。杰西凭借其出神入化的枪法和经历成为平民百姓心中的传奇人物。人过中年杰西逐渐厌倦颠沛流离和与政府捉迷藏的生活，手下的喽罗或死或伤，兄长也因杰西的坏脾气选择离开。新加入“詹姆斯帮”的懦弱男孩罗伯特•福特（CaseyAffleck凯西•阿弗莱克饰）视杰西为超级偶像，与渐感疲惫的杰西隐居乡间。然而经过多年的相处，罗伯特却最终成为这名传奇侠盗生命之闸的掣动者……
Ellen Carter's career is on the rocks. She hasn't written a worthy novel since her husband went missing and she was suspected by the police of murdering him. To top it all off, she has reason to believe that her new tenant Leslie Steckler is the serial killer responsible for a number of deaths in the region. But what she doesn't know is that, in the meantime, Steckler has discovered a little secret about her...