军政府统治下的缅甸，其西部由于蕴含丰富资源而被军队觊觎多年，那里的儿童经常被军队强征入伍，针对平民的屠杀已经成了部分军人的娱乐……一支教会义工小队为了进入该地区向难民提供人道主义帮助，在泰国找到了隐居的兰博（西尔维斯特•史泰龙 Sylvester Stallone 饰），希望熟悉河道的后者提供帮助。兰博认为时局没有改变的可能，拒绝带路，但终被义工莎拉（Julie Benz 饰）的诚意打动，将他们送达。 岂料这支义工小队在村庄中遭到军队的袭击，生还者全部被掳走。教会获悉义工们身陷险境，组织雇佣兵营救，并再次委托兰博带路，这一次，兰博的态度发生了转变，他率领雇佣兵们潜入缅甸军营，又一次化身热血战士。
Plot Summary:Vietnam veteran John Rambo has survived many harrowing ordeals in his lifetime and has since withdrawn into a simple and secluded existence in Thailand, where he spends his time capturing snakes for local entertainers, and chauffeuring locals in his old PT boat. Even though he is looking to avoid trouble, trouble has a way of finding him: a group of Christian human rights missionaries, led by Michael Burnett and Sarah Miller, approach Rambo with the desire to rent his boat to travel up the river to Burma. For over fifty years, Burma has been a war zone. The Karen people of the region, who consist of peasants and farmers, have endured brutally oppressive rule from the murderous Burmese military and have been struggling for survival every single day. After some inner contemplation, Rambo accepts the offer and takes Michael, Sarah, and the rest of the missionaries up the river. When the missionaries finally arrive at the Karen village, they find themselves part of a raid by the sadistic Major Pa Tee Tint and a slew of Burmese army men. A portion of the villagers and missionaries are tortured and viciously murdered, while Tint and his men hold the remainder captive. Concerned by their disappearance, the minister in charge of the mission gathers a group of mercenaries and pleas Rambo transport them with his boat, since he knows their last exact location. But Rambo can't stay behind: he joins the team where he belongs, to liberate the survivors from the clutches of Major Tint in what may be one of his deadliest missions ever
