Detective's movie plot

Within a few days, three "smiling murders" shook the city. During the investigation, Wang, a young detective and policeman "clown", made an amazing statement: this is a serial murder! So, he and his partner Huang Feihong started a thrilling journey of "catching the murderer". Huang Feihong always seems to make an own goal, but he is actually a real kung fu master. At every critical moment, he can always help Wang save the day. During the investigation of the case, Wang first targeted the suspect as a female star. With the deepening of the case, her suspicion was gradually ruled out, and her sister Dai and others became the suspects of Wang. Finally, Wang decided to pretend to be her boyfriend to lure the murderer out. At the same time, the danger is slowly approaching the king, the truth will soon be revealed to the world, and the ultimate confrontation between the king and the murderer will begin.