Lin Yan, a recognized genius detective of the A City Criminal Investigation Detachment, has repeatedly solved strange cases with his amazing sense of traces and smells. He has been repeatedly called upon to take action even in unsolved cases across provinces.
A murder in a secret room on a snowy night broke the tranquility. The scene was so clean that it was almost eerie, leaving only a fingerprint with a triangular mark and a message with unknown meaning. As the investigation deepened, this case was actually connected to many unsolved cases across the country, and a serial murderous figure with unpredictable whereabouts and extraordinary tricks emerged.
He was assigned to a special task force of the provincial department and went to various places to hunt down the murderer. Through investigation, reasoning, control, and profiling, he is getting closer and closer to the truth, and also closer and closer to the abyss.
The seniors who trust him, the lover who cares about him, the opponents peeping in the dark, the encirclement that tightens step by step... Everyone is waiting for the murderer to be caught.
No one knows that in this hunt across several cities, the person who knows the murderer best has already been deeply involved in the chess game.
It wasn't until the last page that the mystery was revealed
