Episode 12 begins with Jung-won at her apartment with Woo-jae, watching the tape of a man stabbing Eun-sae. That’s when Woo-jae enters, wearing a black hat and jacket. Jung-won asks him to go buy a cake for her father’s death anniversary and checks his car. She realizes he had gone to Mueon and there’s mud on his shoes. When he returns, they hold a small ceremony for her father. Woo-jae tries to talk to her but she goes to bed. In the morning, she wakes up from a nightmare. When she reaches Ae-na’s apartment, Tae-heon is waiting for her. He’s headed to Mueon to find Na-ri. He suspects the body found as Lee Na-ri could be a missing female immigrant. Tae-heon then holds Jung-won’s hand and tries to cheer her up.
Later, we see Tae-heon meet a woman whose friend, Jang Hwa-lan, went missing around the time of the Bongto fire. She had a part-time job at Bongto plant on the day it caught fire. Afterwards, the local detective offers to find the 911 calls from that day. Tae-heon also learns that Mujin Resort was built in place of the Bongto plant and it became a huge success. Lee Ba-reun comes home to find a note from Jung-won. She tells him about Na-ri and asks him to contact her. In Mueon, Tae-heon comes across the bus stop where he and Jung-won had spent some time. He sends a picture to Jung-won, who seems conflicted. She then goes to the building of Woo-jae’s office and learns that there is a back alley connected to the cafe in that building — Soo-rin’s cafe. Which means Woo-jae’s alibi isn’t airtight.
Jung-won then gets a call from Ba-reun and convinces him to meet. She tells him about the missing female immigrant. She also accuses Ba-reun of ensuring Jung-won was the first to find Jin Myung-sook’s body. Ba-reun then reveals that he met Jung-won’s father, Sang-gyeon.
A flashback shows Sang-gyeon interviewing Ba-reun and his family. Later, Ba-reun heard Sang-gyeon confronting the murderer on the phone. A few days later he was murdered.
Ba-reun promises to talk to Jung-won again, once he’s found more, and leaves. Elsewhere, Pan-ho is happy to hear that Woo-jae is going to become a father. Woo-jae asks to be put in charge of the second Mujin resort. He later burns the photograph of him with Na-ri and Yoon-young. As well as the vinyl she gave him.
Woo-jae messages Jung-won but she simply switches off her phone. She then goes to a women’s clinic. Secretary Gong enters Woo-jae’s office and tells him something. He rushed to the clinic and berates Jung-won for getting an abortion but she says she didn’t get it.
They go back home and Jung-won tells Woo-jae about her mother. She had left Jung-won when she was very young. After her father died, Jung-won visited her but didn’t receive any comfort. Now, she’s kept the baby because she doesn’t want to be alone in life. Woo-jae asks her to push the divorce until she gives birth.
Tae-heon tries calling Jung-won but she doesn’t pick up. Woo-jae comes to meet him instead. He tells Tae-heon that Jung-won is pregnant and asks him to not make things difficult for her.
Tae-heon is quite shaken by this news. He calls Jung-won and they meet. Before she can say anything, he declares that he loves her. She says her feelings have changed since she realised she’s pregnant. He still wants to be with her but she tells him to forget her previous confessions.
Back home, Ae-na offers Jung-won some comfort. Tae-heon is drinking his sorrows away and finds himself joined by Secretary Gong. He advises Tae-heon to not hold on to something that has no future.
Meanwhile, Mo Hyung-taek has been enthusiastically campaigning for his position in Gangwon Province. Secretary Song tells Mo that the police are looking for the real body of Lee Na-ri. At the police station, Tae-heon listens to a 911 call on the day of the Bongto fire. The man on the phone says his friend has passed out.
After visiting the Bongto detective, Mo seems really happy. Pan-ho then calls him and the two meet. Pan-ho is in a good mood because of the news of his grandchild. But that’s quickly defused when Mo Hyung-taek reveals his suspicion about Lee Na-ri escaping the factory. The assemblyman also has access to the 911 recording currently in Tae-heon’s possession. He insinuates that the man on the phone is someone Pan-ho knows.
A flashback to the day of the fire shows Seol Pan-ho and Mo together. Mo is definitely in a higher position of power at the moment. Pan-ho seems stressed about something. Later, Mo notices the front headlight of Pan-ho’s car is broken.
Back in the present, Jung-won looks at the video Yoon-young left her. She remembers a moment from the past when Woo-jae said he didn’t want to go to New York for a holiday. He said he was very lonely when he was studying there. Jung-won’s father died in January that year and Woo-jae left for the US in February.
Jung-won visits Mo Soo-rin and asks her if she knows about Woo-jae’s movements in January of that year. Soo-rin says she doesn’t remember but it could be in her diary. Jung-won asks Myung-soo to check the diary and asks him to not tell Tae-heon. Myung-soo checks and tells Jung-won that according to the diary, Yoon-young visited Woo-jae in a hospital in Seoul on January 10th.
Woo-jae gets a visit from Pan-ho and tells him Tae-heon has the 911 recordings from 2009. This disturbs Woo-jae greatly, to the extent that he hallucinates a dead body while driving home. A flashback shows young Woo-jae hitting Lee Na-ri with his car at the episode ends.
