In the busy and noisy Chinatown, there is a man who calls himself "The First Detective“". He is Qin Feng's distant cousin, Xiao Tang.Although his reputation spread among the neighbors, in fact, his detective skills can often only be described as ” Lame “.

Xiao Tang, whose real name is Tang Mou, suffered a heavy blow due to a failed marriage when he was young.His wife betrayed him at the wedding, which made him frustrated. In anger, he left his hometown and came to the exotic land of Thailand.Although his detective career was not satisfactory, he managed to make a name for himself in Chinatown with his fluent Thai and a little knowledge of Feng Shui.

Xiao Tang has a characteristic that he is particularly concerned about his own image.He asked his nephew Qin Feng to call him ”Xiao Tang%, trying to give people the impression of being young and promising.Although time has left traces on his face, he still refuses to accept old age.He is greedy for money and lustful, and is often tempted by trivial gains, but he also has his own bottom line and principles.

Xiao Tang once learned Mojia Quan, but his martial arts skills were not superb and he used more dirty methods to deal with difficulties.Despite this, he can always play an unexpected role at critical moments.

By chance, Xiao Tang and Qin Feng teamed up to solve the Bangkok gold case, which improved his reputation in the detective world.Later, they solved the New York serial murder case together, which made Xiao Tang's reputation skyrocketing.

However, all this glory did not satisfy Xiao Tang.He craves more challenges and adventures.Just as he was about to show off his talents in Chinatown, a phone call from Noda Hao disrupted his plans.Noda Hao is a well-known detective in Tokyo. He invited Xiao Tang to go to Tokyo to help investigate a difficult case.

Although Xiao Tang hesitated, he finally decided to accept the challenge.He knew that this would be his best chance to prove himself.So, he packed his bags and embarked on a journey to Tokyo with Qin Feng.