Cui Tiejun, Xu Guozhu and Pan Jianghai, who claimed to be “ trident of the municipal bureau, found that the key suspect was involved in a murder case twenty years ago when they solved a pyramid scheme case.In order to thoroughly investigate the case, three old policemen set up Trident Studio with the support of Bureau Guo.With the cooperation of his apprentice Xiao Lu and the young female police officer Xu Man, the three elders assisted various police officers to solve many major and important cases, and the mystery 20 years ago was finally revealed.

However, as the investigation deepened, Trident found that all this was related to a criminal group called Aoyama Ao ”.This criminal group tries to monopolize the market and gain profits through virtual currencies such as “Yun Trade Coin”.In the end, the trident faced difficulties and broke through many obstacles, finally uprooted the criminal organization that had been entrenched in Ping'an Province for many years, and the main culprit Zhou Mao was arrested and brought to justice.The trident once again protected the lives and property of safe people.