Introduction: The film tells the story of the New Fourth Army soldier Yang Haotian leading the lagging comrades-hygienist Douhuaer, soldier Xiaohu, Feng 451 and others when they returned to the team, and met Qin Yu, a national intelligence agent pursued by the Japanese army, in Miyun Mountain. . With the help of Orion’s daughter Sanxi, the two parties, from hostility to cooperation, jointly resist natural dangers and fight against the Japanese army. Everyone used their respective strengths to successfully prevent the Japanese army from tracking and intercepting the plan, gaining valuable time for the smooth delivery of intelligence. Eventually Yang Haotian returned to the team and Sanxi joined the New Fourth Army and continued to fight on the front line of China's revolutionary cause.