In 1937, the city of Nanjing was in turmoil, the Japanese army was approaching, and undercurrents from all sides were surging. Su Wanqing, a student at a church school, was spotted by Chen Mo, an underground party intelligence agent disguised as a manager of a foreign bank, because of his photographic memory, and was involved in dangerous intelligence transmission work. She relied on her memory to memorize coded telegrams silently, conveying secrets in the streets where cheongsams and rickshaws shuttled; while he, wearing suits and leather shoes from a foreign company, dealt with Wang's puppet spy Zhao Lifu. In troubled times, the two people gradually developed a deep love from their initial cooperation and trust. They walked on the edge of the knife time and time again, evading pursuit, destroying intelligence, and guarding their home and country with their youth and blood. On the eve of the fall of Nanjing, they broke through many obstacles and went to Chongqing together, continuing to write their deep love and faith in the turbulent times in the flames of the Anti-Japanese War.
