After a long absence John Rambo (Sylvester Stallone) is back. He has been living in Thailand, in a village not far from the borders of Burma, which is ruled by an iron-fisted dictator Than Shwe. He spends his time capturing snakes and transporting people on his boat, but when he is approached by a missionary group asking for passage to Burma he doesn't want to take them. One of the missionaries, Sarah Miller (Julie Benz), manages to convince him to help. Along the way Rambo kills a boat of pirates who want Sarah in return for the safety of the rest. Eventually they arrive in Burma and Rambo returns home, only to be approached ten days later by the missionaries' pastor in hopes that Rambo will lead a group of mercenaries to help save the missionaries. Rambo is soon embroiled in all out war with the Burmese army that has captured Sarah and the missionaries and must use all of his guerrilla skills to help the group survive.