Top forensic pathologist Kang Min-ho is about to retire so that he can spend time with his daughter who has just returned home after a long stint overseas.

But when the dismembered corpse of a young woman, identified as Oh Eun-ah, is found at a local river, Kang agrees to do one last job.

The primary suspect is environmental activist Lee Sung-ho, who readily admits his guilt to rookie detective Min Seo-young, Kang's former student.

Kang cries in agony as flashbacks show the graphic autopsy, where he continues to dissect his daughter's corpse and tampers with it by adding semen, completely unaware at the time.

Min begs Kang not to kill Lee for his daughter's death, but the doctor takes out her gun and shoots him.