The War to Resist U.S. Aggression and Aid Korea has entered the most critical decisive stage. During the negotiations at Panmunjom, the U.S. military secretly mobilized a large number of troops and launched a surprise attack. The U.S. military's goal is very clear, which is to capture Shangganling and use it as a stronghold to seize the Five Sacred Mountains and increase the bargaining chips at one time. Guarding Shangganling is the Eighth Company of a certain unit of the Chinese People's Volunteer Army. Faced with many more enemy troops than ours, the volunteers did not retreat, but chose to resist stubbornly to delay the U.S. military and smash the enemy's conspiracy. Led by the company commander Zhang Zhongfa (played by Gao Baocheng), the company fought bloody battles with the U.S. military. Although the environment in the tunnel was harsh and faced the danger of water and food shortages, the volunteers held on for 24 days, laying a solid foundation for the Sino-North Korean coalition's counterattack.