I Just Graduated and Became a Detective, and I Met a Corpse on My First Day.

Lin Zhixia, a new female police officer who has just joined the serious crime team, accidentally touched a dusty old scabbard with her fingertips while sorting out old evidence from ten years ago, and accidentally pulled out a secret clue that had been hidden in the police station for ten years. Following the half-piece of glue residue left at the scene of the secret room murder, the seven crooked carvings on the blade of the deceased, and the unusual details of the arrested suspect publicly complaining about his injustice, seemingly independent murders gradually intertwined. Lin Lan overturned the team's conclusion based on the tiny traces scanned in the seams of his shoes. It was not until the seventh mark pointed to the seventh life that the team was shocked to realize that they had fallen into a carefully arranged game within a game since the first case. The lights in the office suddenly flashed three times, and on the surveillance screen in the corridor at the door, a figure in a black raincoat flashed past quickly - the mole hiding in the dark was finally showing his true identity.