The story is set in 1954 as the remnants of the Yunnan Anti-Communist National Salvation Army made up of survivors of Chinese Nationalist troops were preparing to disarm and be repatriated to Taiwan. Upon disarming, the Burmese military attacks one of the camps, causing the survivors to defect or flee to the mountains for refuge. Many of these men end up fighting for the various partisan and bandit armies in the area.

Those who stay behind to fight the Communists end up joining forces with the Thai military. One of the soldiers, Ke Bao-den (Chung-Hua Tou), is particularly distraught to hear that the joint force will first do battle with the army of the bandit Lo Huei (Ray Lui), because some former comrades are part of his force, including Bao-den's friend Fan Long (Tony Leung Chiu-wai). Fan Long had saved Bao-den's life in a Burmese prison camp, so the soldier decides to return the favor, undertaking a traitorous and potentially fatal mission to warn his friend about the planned attack.