Former forensic official Yiren welcomes his daughter Jiang Xiaomeng out of the nursing home. The father and daughter start a new life together with Xu Haiyin, a journalist who turned into a foundation public relations officer. However, they are involved in a series of deaths, and Fang Yiren becomes the number one suspect.The case leads to a murder case he handled 15 years ago. The reputation of his mentor Lin Jingrui is also questioned. He must cooperate with detective Zhao Chengkuan and forensic doctor Xue Xinning to find out the truth and clear his name, otherwise he will lose his home with Xiaomeng again.

After attending his mentor's funeral, Fang Yiren returns to the police station and finds himself involved in two murders 15 years apart.

Fang Yiren's independent investigation heightened his suspicions, and Xu Haiyin received an unusual job offer from the Qiye Foundation.

The police tracked a man named Wu Junlu based on clues in an old photo.Later, Fang Yiren met Xu Haiyin in Qiye.

Xu Haiyin begins to question Lin Mingcheng's character, while Fang Yiren uncovers more disturbing clues that point to a man he admires.

After investigation, it was discovered that the serial killings were related to a crime in the past.Xiaomeng did a lot of work to help solve the case, but was ignored by Fang Yiren.

The search for an abandoned bus brings police closer to the truth.Fang Yiren and Xu Haiyin asked Mingcheng what happened 15 years ago.

A new suspect appeared, and the direction of the investigation changed dramatically. Fang Yiren had to race against time to find the serial killer.

Fang Yiren, whose life hangs on a thread, is in danger and must survive.Meanwhile, Xiao Meng and Xu Haiyin must risk everything to save their loved ones.