Su Ming, a trainee security officer, has simulated crimes 100,000 times in his dreams and acquired god-level disguises, psychological profiling and other incredible skills. On the first day of reporting, he relied on his extraordinary insight and teamed up with the capable and valiant captain Shen Lin (also the chief medical examiner) and his honest and loyal partner Wang Hu to solve major cases in a row. From the suspicion of a fall on campus to the unsolved case of corpses that had been buried for 20 years, Su Ming used the thinking of a "criminal" to trace backwards and uncover the mystery of the highly intelligent criminal organization "K" step by step. When the perverted killer and the ghost murderer were arrested one after another, the real mastermind was sneering in the shadows - this cat-and-mouse game has just begun.