Cheng Youning is a forensic expert, calm and meticulous, but he personally burned the key evidence - the blood-stained silver ring - overnight. The whole city was in an uproar, public opinion was boiling, and she was pushed to the forefront. The only person who believed that she was not crazy was her former partner Shen Lingyao, who was sent to prison by her own hands. In that unsolved case three years ago, the deceased was Shen Lingyao's twin sister. Now that the evidence has disappeared, the truth has begun to flow against the current. Cheng Youning's fire burned not evidence, but lies; Shen Lingyao's smile didn't hide hatred, but a plan. When the surveillance camera captured the moment Cheng Youning turned around, in the firelight, she whispered: "You knew earlier, right?"
