Cha Young-jin is a detective. She lost her friend 19 years ago to a serial killer. Cha Young-jin still carries guilt and trauma over the death of her friend. The serial killer case then begins again after 19 years. Cha Young-jin chases after the killer.
Eun Ho gives the money he'd kept in a pair of sneakers to Dong Myung. Eun Ho falls from a hotel building, and Young Jin feels guilty for not having given him chances to talk to her about his situation. She thinks of it as a criminal case and starts investigating the traces he left, and Sun Woo accompanies her.
After Eun Ho told Young Jin everything he remembers, Young Jin is sure that Sang Ho is the killer. However, she doesn't have any evidence to prove it. With the book left to Eun Ho by Ki Ho, she tries to find out the secret behind it. Meanwhile, the result of the disciplinary hearing comes out.
Young Jin now knows whose money Eun Ho took from the hotel’s bathroom. Sun Woo who finds out Min Sung’s wrongdoing needs to make a choice. Jang Ki Ho disappeared leaving his cell phone and wallet at home, and Baek Sang Ho and Yoon Hee Seob are trying to find him.
Kevin Jung, one of the two that are involved in the drug dealing in the Millennium Hotel, is found dead. Young Jin is after Lee Young Sik. Superintendent Han and Sun Woo visit Min Sung at the hospital. Dong Myung meets with Tae Hyung and tells him about the old man who was looking for Eun Ho the other day.
Young Jin starts to dig into Eun Ho’s case and finds a button that fell from Eun Ho’s school uniform in the crime scene. She realizes this case is somewhat similar to the stigmata case. Superintendent Han tells Young Jin to choose only one case to investigate between Eun Ho’s case and the stigmata case. Chairman Baek visits New Life Church.Watch Now:iTunes
Young Jin notices that what’s happening around Eun Ho is all related to the late Seo Sang Won. Eun Ho starts to react to strong stimuli, yet remains unconscious. Sang Ho decides to punish Lee Young Sik and Kevin Jung who used his hotel for drug dealings. Sun Woo runs into the caregiver of Eun Ho, and it reminds him of something.
Young Jin realizes that Eun Ho fell because of the stuff Jang Ki Ho asked Eun Ho to keep and starts to question people around Ki Ho. Dong Myung is about to be transferred to another school. Sang Ho learns that Jae Chun has been hiding Ki Ho and makes a deal with him to find out what Ki Ho gave to Eun Ho.
Sun Woo finds a decisive clue on the rooftop of the Millennium Hotel and realizes that Eun Ho jumped off himself to survive. What happened on the day Eun Ho fell is revealed including who took Eun Ho to the hotel from the abandoned building and how Dae Hoon, the chauffeur of Min Sung, died.
Eun Ho starts to regain his memory of the last one month. So Yeon meets with Chairman Yoon of Shinsung High School. Young Jin meets with Ki Ho and decides to cooperate with him to find the stuff Ki Ho left Eun Ho with and reveal Sang Ho's secret. Tae Hyung runs into Sun Woo at the hospital Eun Ho stays.Watch Now:iTunes
Jin Young finds Seo Sang Won, the culprit of the stigmata serial murder case, on the rooftop of the building. He claims he has rather blessed the victims and falls from the building and kills himself. Eun Ho receives an award for his good deed of saving an unconscious guy, and feels threatened for some reason.
The truth of the eighth stigmata murder case that took place 20 years ago starts to be revealed. Eun Ho tells Young Jin about what he saw in Sang Ho's study at his hotel. He also confesses the shocking truth about his parents that he'd been hiding. The police hold a disciplinary hearing on Young Jin.
Eun Ho regains his consciousness but doesn't remember what happened in the last one month. Now everyone knows that the eighth victim of the stigmata case was Young Jin's friend, and Young Jin is prohibited from investigating any case. Hee Seob tries to cover up Min Sung's leakage of the exam answer sheet and makes an appointment with Eun Ho's mother.Watch Now:iTunes
Young Jin and Soo Jung are close friends. One day, Young Jin ignores Soo Jung's phone calls, and Soo Jung is found killed by a serial killer. On her way home from the police station, Young Jin gets a phone call from the murderer of Soo Jung, and she warns him that she'd find him no matter what. Young Jin becomes a detective.
Dong Myung who is related to the money Eun Ho found goes missing. Young Jin and Sun Woo track down Dong Myung. Baek Sang Ho continues to offer everything to Eun Ho and his mother. Jae Hong and Ja Young find out a strange room at Ha Min Sung, Eun Ho’s classmate’s chauffeur, Choi Dae Hoon’s home. Dong Myung opens up and starts to tell about Eun Ho.Watch Now:iTunes
Sang Ho breaks into Eun Ho's ward and threatens him that he'll kill his mother. He takes Eun Ho to the rooftop and calls Young Jin to come for him. Young Jin confronts Sang Ho on the rooftop. They tell each other about what happened until now and listens to all the stories about Sang Won.
The secrets are finally revealed including the fact that Sang Ho killed Hee Jung. Ki Ho helps Young Jin with her investigation. The detectives find out what Doo Seok was up to, and they arrest him. Ki Ho decides to return to the church and make a speech about what happened to him.