Flashback…Baek Hee Sung brings a pregnant Cha Ji Won to their new home. She's thrilled. She suggests he talk to the baby. Hee Sung awkwardly complies. She notes he's always giving to her. She asks if he wants anything from her. He does.
Ji Won is surprised to find her husband at the apartment of Reporter Kim Moo Jin . Hee Sung lies that he's helping Moo Jin understand about metal craftsmanship like Do Min Seok (Do Hyun Soo's Father) was. Ji Won asks why Moo Jin lied about the meeting. Inside the apartment, Do Hae Sue (Do Hyun Soo's sister), listens to Moo Jin lie that he didn't mean to keep it a secret. Ji Won walks into the apartment. Do Hae Sue greets her. Ji Won doesn't remember her. Do Hae Sue prompts her. Then Ji Won remembers. Do Hae Sue shares she's helping Moo Jin to find the accomplice. Ji Won sees the evidence board. Hee Sung tells Moo Jin to make his wife coffee. Everyone watches Ji Won study the evidence board. Moo Jin brings coffee for all. Ji Won suggests they work together to find the accomplice. She asks what "the trap" means. Moo Jin says Do Hae Sue thought Do Min Seok might set traps. Hee Sung suggests they listen to the voice recording left by the accomplice.
The real Hee Sung wakes from his coma. His parents, Baek Man Woo and Gong Mi Ja are shocked. Hee Sung tells his mother it wasn't her fault. She cries. He asks what happened to the person he hit with his car. The Baeks are taken aback.
They ask Ji Won what the background sound in the voice recording could be. She notes the police will analyze the background noise. Do Hae Sue stands to leave. Ji Won asks if Do Hae Sue wants the accomplice caught. Do Hae Sue counters anyone would. Ji Won counters the accomplice could be Hyun Soo. Do Hae Sue is sure it wasn't her brother. She reveals she met with a therapist who said that a young Hyun Soo had no emotional feelings. Ji Won believes an adult Hyun Soo would be a manipulative master. Do Hae Sue defend her brother. She starts down the path of admitting she killed the foreman. Hee Sung "accidently" spills coffee and breaks the moment. Moo Jin declares he wants everyone to leave.
Hee Sung drives his wife home. He apologizes for not telling her he was working with Moo Jin. Ji Won says she doesn't tell him everything either.
Do Hae Sue tells Moo Jin she wants to be hypnotized to recall the accomplice's face. She wants to clear her brother. Moo Jin suggests they hang out like they did when they were young. Do Hae Sue wants to help her brother now like she didn't do when they were young. She leaves.
Ji Won recalls Detective Choi Jae Sub (Choi Young Joon) belief that Hyun Soo met the accomplice. She asks her husband if he were Do Min Seok, how would he give the car key to his accomplice. She shares that the police believe Hyun Soo might have created an alibi for his father. That means either Hyun Soo gave the car key to his father's accomplice or Do Min Seok did so without Hyun Soo's knowledge during the day of the murder as they went from gallery, to eatery, to bar, and to the movie theatre. She asks if Hyun Soo met the accomplice. Distracted Hee Sung almost goes through a red light but Ji Won prompts him. He notices she's not wearing her ring. Ji Won lies she took it off to wash her hands. She notes not having it isn't so bad.
The housekeeper is happy for Mrs. Baek.
Mr. Baek tends to his son. He tells him he handled man he hit. Hee Sung asks why his father didn't answer his calls. Mr. Baek claims he was busy. Hee Sung asks if work was more important. Mr. Baek lies it wasn't. Hee Sung ask if he'll be able to walk again. Mr. Baek declares his son will be able to live a normal life.
Baek Eun Ha (Hee Sung's daughter) is thrilled to have a rooftop party with her parents. Ji Won watches her husband engage with Eun Ha. Ji Won notes this party was effort. Hyun Soo says he enjoyed doing it. Ji Won gives an underhand thank you.
Flashback…Hyun Soo tells Do Hae Sue that he doesn't love his wife.
Ji Won gets a call from recording the background noise of the recording. She asks the analyst to send her the recording via email. She tells her husband after removing the static, the analyst heard another man's voice. She gets the voice recording and plays it. They listen to a man ask if another would like an ashtray. Hyun Soo is riveted.
Flashback…Hyun Soo and his father are at the bar. The bartender asks Do Min Seok if he'd like an ashtray. Do Min Seok confirms he would. The bartender chips ice with a tool.
The chipping ice is the same sound as the voice recording.
Flashback…Hyun Soo looks at the bartender as he chips ice with a tool. He remembers his father's jacket knocked from the back of his chair by a man in a hat. The man retrieves the jacket and gives it to his father. He leaves.
Ji Won asks why her distracted husband is standing. Hyun Soo claims it is nothing. He sits and engages his daughter. Ji Won wonders what is going on.
While they wash dishes, Hyun Soo asks what is going on with his wife. She says she doesn't feel the same about him anymore. Hyun Soo what she means. Ji Won says after 14 years, things change. She asks if he feels the same about her. Hyun Soo says he does. Knowing that means he doesn't love her, she's not pleased. Hyun Soo suggests work is stressing her out. Ji Won admits she's been wonder about a life if they broke up. She tells her husband that there wasn't a reason she fell in love and there isn't a reason she's fallen out of love. She claims she doesn't like him anymore. She tells him not to try and please her anymore. Hyun Soo asks why she's crying. Ji Won says this is a hard conversation. Hyun Soo admits he doesn't understand what she's saying. Ji Won declares she wants to break up. Hyun Soo asks what he can do to make it right. Ji Won tells him he can't do anything, it's over. Hyun Soo can't believe it.
In the bedroom Hyun Soo wants to talk. Ji Won says she has to work. She says working Do Min Seok cases makes her guilty. She wants to solve the cases but she doesn't know enough. Hyun Soo tells her to take a step back. Ji Won knows that he helped her deal with stress in the past, but now he causes her stress. She leaves.
Moo Jin can't believe it when Hyun Soo shares that Ji Won doesn't love him anymore. Hyun Soo admits he feels lost. The doorbells rings. Do Hae Sue arrives and asks her brother what is wrong. He wonders what he must do to get back in good graces with his wife. Moo Jin declares Hyun Soo must declare his love and sweep her off her feet. Hyun Soo believes if he helps catch the accomplice, this will solve his problem. Moo Jin quips most men don't resolve relationship issues by solving their wife's serial killer case. Do Hae Sue notes her brother cares deeply for his wife. She notes he's hurt by the idea of not having his wife in his life. Hyun Soo shares he knows what the background sound was. But first he has to check it out. He tells his sister not to spend too much time with Moo Jin and leaves. Moo Jin suggests they hang out. Do Hae Sue asks him to take her home.
Hyun Soo sends another text to his wife. She doesn't answer. He scrolls through their previous texts. He closes his eyes.
Ji Won tells Detective Choi, Officer Im Ho Joon , and Team Lead Lee Woo Cheol they need to set a trap for the accomplice. She offers to be the bait. Detective Choi and Officer Im agree. Team Lead Lee considers then agrees.
Moo Jin follows Do Hae Sue into her apartment. He's surprised it is spartan. She admits she lives simply, sleeps fitfully, often doesn't leave her apartment. She tells him she's a broken woman and they can't go back. She asks him to leave. Moo Jin complies.
Hyun Soo goes to the bar he and his father visited on the fateful night. He recognizes the tattoos on the bartender's arm. He notes he came here with his father when he was young. The bartender pours him a drink on the rocks. Hyun Soo notes when he came with his father, the bartender chipped the ice by hand. The bartender shares they only do that for special customers. Hyun Soo says he's looking for someone that must a special customer. He plays the accomplice's voice recording. The bartender has a reaction. He claims not to know the voice. Hyun Soo asks the bartender to call should he remember. Claiming not to have a pen, Hyun Soo asks to borrow one. He stares at the proffered pen.
Flashback…Hyun Soo's father asks his opinion which pen to give a special friend who always gives him good raw material. Hyun Soo points out his father usually gets his own raw material. Hyun Soo's father counters that some raw materials have too much risk. Hyun Soo asks for details but his father declines. Hyun Soo picks the pen he'd choose.
Hyun Soo looks at the bartender while holding the pen.
Ji Won makes the calls while everyone listens. She calls about a job and shares she has bad credit. She's told that isn't a problem.
Hyun Soo asks the bartender if he knew the voice. The bartender claims he doesn't. He asks if he knew Do Min Seok. The bartender claims he doesn't. Hyun Soo hops the bar and tells the bartender the pen is an art piece crafted by Do Min Seok. The bartender claims he doesn't know anything. They struggle. Hyun Soo demands the bartender tell all.
Ji Won is surprised when the potential employer says they'll meet in the hotel Ji Won claims she's staying at. The team wonders if this is the break they are waiting for. Officer Im has a bad feeling about it.
The woman who works for the employment agency tells CEO Yeom Sang she has their next easy target. CEO Yeom has a bad feeling about it. He doesn't want to get caught. She assures him she won't. He gives her part of her cut of the money. More will come when it is sold. The bartender calls CEO Yeom and reports they have a problem. Hyun Soo grabs the phone and asks if he's Do Min Seok's accomplice.
The real Hee Sung falls out of bed. His mother finds him on the floor. He tells her he was on his way that night to meet someone. He wants to meet that person now. He asks for her help.
Mr. Baek looks at a flip phone.
The bartender brings Hyun Soo to the employment agency. He opens the door.
The woman that works for the employment agency knocks on Ji Won's hotel door. She opens the door.
Do Hae Sue stares into the night. Moo Jin arrives with items to fix a broken light.
Hyun Soo tells CEO Yeom he's Do Min Seok's son. CEO Yeom asks for the drink his father ordered at the bar. Hyun Soo says his father called in advance. CEO Yeom looks him over and says he looks like his father. Hyun Soo asks if CEO Yeom knew his father's accomplice. He's told that's a line that won't be crossed. CEO Yeom notes Hyun Soo is a wanted man. Hyun Soo points out that's why he wants to find the accomplice. CEO Yeom says Hyun Soo should be afraid of the accomplice. Hyun Soo tells him relay the message that he's not afraid of the accomplice. He agrees to help for the right price.
Ji Won tells the woman that she's alone in the city. The woman assures her she can make good money by delivering items. Team Lead Lee and Detective Choi listen to the conversation. Ji Won asks what she'll need to deliver. The woman asks for cash. Ji Won gives her what she's got. The woman promises she'll make much more than this. Ji Won tells the woman the law she just violated. The woman demands to know who Ji Won is. Ji Won claims she's Jung Mi Sook. Detective Choi knows that phrase means action and exits the car. When Detective Choi and Officer Im arrive, the woman jumps to a neighboring room's balcony. Unfortunately, with the handcuffs she can't hold on and falls to the ground.
Hyun Soo offers an amount. CEO Yeom wonders which man will give him more money. He says he can't betray his client. Hyun Soo asks if CEO Yeom sold raw materials to his father and the accomplice. CEO Yeom confirms this. He tells Hyun Soo he's going to turn him over to the accomplice.
The chief yells at Ji Won for the situation. Team Lead Lee says this is his fault. The chief yells the woman could die. Officer Im calls and says the surgery is underway.
Ji Won steps outside. She remembers happy moments with her husband. She looks at the texts he sent her that she didn't respond to. She remembers what Hyun Soo asked for all those years ago.
Flashback…Hyun Soo asks his wife to never stop loving and trusting him. Ji Won says that's easy. Hyun Soo vows to live for her.
Ji Won cries. She murmurs she misses him.
CEO Yang's thugs hold him while CEO Yang prepares a special drink. CEO Yang says it's too bad that he has to do this. He promises that when Hyun Soo wakes up, he'll be face to face with the accomplice. Hyun Soo doesn't want to drink. He offers to become a client. That gets CEO Yang's attention. CEO Yang asks if Hyun Soo knows what he sells. Hyun Soo replies people. CEO Yang says Hyun Soo's father claim his son was like him, but he's not sure it included this area.
Hyun Soo's phone rings. A thug hangs it to CEO Yang. Ji Won is calling. Hyun Soo is given the phone and told to answer. Ji Won tells her husband she wanted to hear his voice. She admits she's had a bad day and wanted to talk to him. Hyun Soo says he's too busy to talk. Taken aback, Ji Won remembers her husband's request for trust. She tells him to answer her questions with a yes or no. She asks if he's okay. Hyun Soo says yes. She asks if he can handle the situation he's in without her help. Hyun Soo says yes. Ji Won tells him he has one hour to come back to her. Hyun Soo realizes what she's saying. She tells him she misses him.