Synopsis：In the early years of the Republic of China, Xiao Jian was arrested on patrol, a boy who dreamed of becoming the number one detective in Shanghai. During the investigation of a series of mysterious cases, he accidentally touched on their so-called control incidents. He became a member of the Special Investigation Bureau inexplicably. A series of thrilling, bizarre and suspenseful events took over the code name of "Broken Army" and became an unknown guardian.