The story takes place in a modern metropolis called "Fog City". Many major mysteries broke out at all levels of society, and the police were unable to investigate them in depth due to various reasons. A group of young people with different backgrounds spontaneously formed the "Qi Mystery Society" to explore the truth. They continue to collide in their work and personal lives, and encounter power undercurrents, moral choices, and human rifts as the team grows. Each volume independently unfolds an intricate case, and at the same time connects each other with a main line that runs through the whole situation - the huge shady secret hidden on the top floor of the city. They experienced the troughs of life and redeemed each other, and finally revealed the ultimate mystery of Fog City.
