After being rejected from the police college, a mannerly man travels to Bangkok where he and an energetic distant relative must solve a murder case.

Driven by the desire for the huge reward, Tang Ren tricked Qin Feng to New York, to attend the World Detective Contest. Later on, behind the crazy competition, Qin and Tang discovered the real hidden facts of this contest.

Tang Ren and Qin Feng travel to Japan to investigate the death of a mafia head. As they suspect foul play, they engage in a battle of wits against foreign detectives.

In 1900, a white woman was murdered in Chinatown in San Francisco, and the suspect was a Chinese man. The murder caused social shock, and people demanded the closure of Chinatown.