The story takes place in the late 1940s. After eight years of the War of Resistance Against Japan, the Chinese nation finally drove away foreign invaders, and the Kuomintang and the Communist Party immediately launched a war to conquer the Central Plains. After a tough tug-of-war, the balance between the two sides was gradually broken. In order to reverse the decline, the Kuomintang tried to set up a spy network in the upper echelons of the People's Liberation Army, hoping to disintegrate our army with this "Sky Strike Plan". Zhan Shouan (played by Yang Shuo), an underground member of the Communist Party of China, was ordered to sneak into the most dangerous situation as a double agent, with the mission of smashing the "Sky Strike Plan". In this process, he not only had to face the pincer attack of senior agents of the Kuomintang, but also eventually broke with his brother, Zhan Shouping (played by Hu Jun), the commander of the new 89th Army of the National Army. Under the waves of the changing times, everyone has become an important chess piece that affects the course of history...