Shandong, 1942. Wang Qiang, a member of the Railway Guerrillas, is tasked with sabotaging the Japanese army’s railway supply lines and supporting the base area’s campaign against the enemy’s encirclement and suppression. He and his comrades plan to blow up a bridge used to transport Japanese military supplies. Heavily guarded by Japanese troops, the bridge is no easy target. Disguised as a railway worker, Wang Qiang sneaks near its supports and plants explosives. When the Japanese discover his comrades, Wang Qiang is wounded while covering their escape.