When the iron-blooded detective Ling Feng met the calm forensic doctor Su Wan, an unexpected reunion spanning seven years quietly unfolded in the smoke of serial cultural relic thefts. There is an unclaimed sketchbook locked in his drawer, and there is a secret memory of "Police Academy Student in the Rain" hidden under her scalpel. When the knot marks at the crime scene coincide with the unsolved case ten years ago, and when the lights of the forensic laboratory illuminate the similar old scars on each other's wrists, can they cut through the fog of time between the sharp edges of the scalpel and the police badge, and let the confession that was seven years late become a light that illuminates the darkness?
