The spring of 1939, the occupied area of Shanghai. The "Jishitang" Chinese medicine shop on the edge of the French Concession is open as usual. The owner, Chen Yanzhou, plays with the abacus and weighs medicinal materials every day. No one knew that this businessman, who seemed to only care about his account books and the quality of his medicinal materials, was deciphering telegrams from all sides every night. A piece of intelligence that the Japanese army was about to wipe out the resistance organizations in the concession accidentally fell into his hands, and the traffic officer who delivered the intelligence was shot dead in the street at the Xiafei intersection. Chen Yanzhou must send out the alarm under the eyes of the enemy within forty-eight hours. But he didn't know that the Special High School had already targeted "Ji Shi Tang", and his opponent was Shinichi Asano, the head of the Japanese spy agency known as the "Fox on Shanghai."
