During the War of Resistance Against Japan, a CCP army unit guarding the southwest border follows what is ostensibly a trading caravan and discovers that these traders are actually smuggling arms and spy equipment to Chiang Kai-shek and his American allies.
The Public Security Bureau intercept a telegram notifying foreign agents to retrieve the "110 secret". Shi Yan, head of the Reconnaissance Section, starts a campaign of counter-espionage, but one of his agents is soon killed on board a train.
Old lady from the countryside travels to the bustling city of Xinjing to join her children in the "10th Anniversary Celebration of the Founding of Manchukuo", and then solves the conflicts within the family.
