In 1935, Ma Jiaqi, the first Chinese criminal detective in the French Concession, after solving the revenge sniper case of the Youth Gang, formed a special investigation team with toxicology expert Ding Chengxin, forensic doctor Song Yaxuan, fighting master Liu Yaowen, agency expert Zhang Zhenyuan, intelligence expert Yan Haoxiang, and socialite He Junlin to guard the precarious Shanghai beach.
