Cui Tiejun, Xu Guozhu, and Pan Jianghai, known as the "trident" of the city bureau, discovered that the key suspects were implicated in a murder case 20 years ago when they cracked a pyramid scheme. In order to be able to investigate the case thoroughly, the three veteran policemen, with the support of the Guo Bureau, established the Trident Studio. With the cooperation of the apprentice Xiao Lu and the young female police officer Xu Man, the old three assisted various police departments to solve many major and important cases, and the truth of the suspected case 20 years ago was finally revealed. However, as the investigation deepens, Trident discovers that it all has something to do with a criminal syndicate called the "Castle Peak Society". And this criminal group tries to monopolize the market and grab profits through the virtual currency of "Cloud Trade Coin". In the end, Trident rose to the challenge, broke through many obstacles, and finally uprooted the criminal organization "Qingshan Society" that had been entrenched in Ping'an Province for many years, and the main culprit was Zhou Mao