In the northern metropolis "Qingjiang City", a reasoning team composed of former police officers, journalists, psychological analysts and technical experts secretly took over various difficult and unsolved cases. From uncovering the true face of serial killers, to digging into the corruption and conspiracies of the powerful, to revealing the subtle crimes in ordinary people's lives, they integrate reason, courage and the light of humanity into every case they solve. The main mystery runs throughout, and the side cases reveal the growth and hidden pain of each member. The team constantly encountered crises and betrayals during the decryption process, and gradually uncovered the truth hidden behind the city. Each volume focuses on a different mystery while advancing the main plot. Eventually all the clues come together to reveal the ultimate mastermind.
