In the 32nd year of the Republic of China, Shanghai fell and undercurrents surged. Xu Zhou, a clerk in the antique street, looks lazy and casual on the outside, but is actually "Zhouzi", a hidden agent of the military command. He uses Juguzhai as his base and conveys secrets amidst the light and shadow of swords. A blood-stained copper coin led to the top-secret plan of "Sakura No. 7", Which turned out to be a deadly poison gas weapon for the Japanese army. Abnormal orders from superiors, the troubles of "Eagle Eye", a ghost in the organization, and the appearance of Lin Wan, the mysterious tea house proprietress, make the situation more complicated and confusing. In order to expose the conspiracy, Xu Zhou infiltrated the concession chamber of commerce, instigated rebellion against senior puppet government officials, and attacked the poison gas factory at night. He and Lin Wan tested each other and fought side by side. Faced with the Japanese army's encirclement and suppression, the assassination of the enemy, and the sacrifice of their comrades, they used their lives as chess, tore through the darkness in the fog of troubled times, and protected their homeland with their blood, vowing to crush the ambitions of the invaders and let light shine on the fallen land again.
