In Shanghai in 1935, there were many concessions and undercurrents from all parties. Military agent Chen Mo sneaked into the French Concession under the alias "Watchmaker" and ostensibly ran a watch shop, but in fact he was performing a top-secret mission related to the fate of the country. When he discovers that his childhood sweetheart, piano teacher Lin Shuyao, has a mysterious connection with the Japanese secret service, a deadly game about loyalty and love begins. With the emergence of a secret blueprint that could change the direction of the war, the Central Unification, Japanese Special Operations, and Soviet intelligence networks were involved in this war without gunpowder. In Shanghai, where neon lights and gunshots intersect, each character wears multiple masks, and the most dangerous enemies are often hidden in the nearest shadows.
