The film tells the story of the anti-Japanese patriots represented by sniper Ren Tianxing (played by Zhang Junhan) who fought a deadly gunfight with the brutal Japanese invaders after the fall of the three northeastern provinces after the "September 18th Incident". The anti-Japanese volunteers led by Ren Tianxing were all killed in a night battle in which they ambushed the Japanese army. Ren Tianxing was seriously injured and was rescued by bandits. From then on, he lived a bandit's life in despair until Bai Ge (played by Kan Xin) who sneaked into the mountain village in disguise awakened him with national justice. In order to save the country and himself, Ren Tianxing cooperated with the anti-Japanese squad composed of Bai Ge and others to assassinate the Japanese virus expert, but the plan was discovered by the Japanese army during the action. How could everyone escape the heavy pursuit? Why did Ren Tianxing set up a tombstone for himself? In the secret investigation of Ren Tianxing and others, the huge conspiracy of the Japanese army to use villagers for live experiments gradually emerged. At this moment, Ren Tianxing received a "declaration of war" from a Japanese sniper. The Tiger Tooth Mountain was filled with smoke. The top snipers from China and Japan were about to fight to the death. What would be the fate of everyone?