The Ultimate Forensic Scientist

Five years ago, a couple was murdered in a killing spree. Luo Qianran, then a forensic assistant, and Tao Su, who had just joined the police force as a psychological counselor, both noticed something suspicious about the case. But because they had to cooperate with the conservative investigation, they did not stand their ground, and a couple they could have saved was killed. They have both carried the guilt ever since. Five years later, Luo Qianran and Tao Su each receive an "Invitation from Heaven." The killer reveals the anticipated date of their revenge. After Luo Qianran goes through a series of cases and setbacks, the killer devises a series of revenge plans for him, trapping him in a desperate situation. The killer's ultimate goal is to utterly destroy Luo Qianran and Tao Su, who failed to stand their ground back then. After several murders, on May 20, Luo Qianran guesses the killer's identity and stops the killer, who is being chased by Mu Wen. He asks the killer not to continue killing after taking his life. He also lies, saying the couple died because of him. Enraged, the killer tries to kill Luo Qianran, but Mu Wen saves him, and the killer takes their own life.