Before the battle of Liaoshen, Communist operative Zheng Chao Yang who had infiltrated the Beiping police had no choice but to retreat after his identity was discovered. In his escape, he was able to take with him a list that can deal a detrimental blow to the Kuomintang.

After Beiping's liberation, Zheng Chao Yang returns to the city. However, waiting for him is a new battlefield. The Kuomintang has dispatched a team of elite spies operating under codename Taoyuan. At the helm is Zheng Chao Yang's older brother Zheng Chao Shan who is a famous doctor.