Se-ri goes missing in the marketplace, but when Jung-hyuk hears she's lost, he buys a candle and holds it up so she can find him. He jokes that it's scented this time, and they both smile in relief. As they walk home, Se-ri admits that Jung-hyuk made her heart flutter a little back there, so he decides it's time to come clean about his situation.
He tells her that he has a real fiancee, but Se-ri acts offended by Jung-hyuk's implication that she has feelings for him, and she (a bit too vehemently) insists that she doesn't. In fact, she says that she has several men in Seoul who are probably crying at her loss, ha.
Meanwhile, Seung-joon drops Dan off at Jung-hyuk's house, which is clearly empty at the moment. She coolly dismisses him anyway, and as he's being driven away, he passes Jung-hyuk and Se-ri. He seems to recognize Se-ri, but he concludes that there's no way she could be who he thinks she is.
Wol-sook and Ok-geum see Dan in front of Jung-hyuk's house and stop to ask what she's doing. She says she's waiting for Jung-hyuk and tells them that she's his fiancee. They're scandalized, since they think Se-ri is his fiancee, so they quickly move on.
Jung-hyuk tells Se-ri that his fiancee is studying in Russia, so she won't mess up their plans. As soon as Jung-hyuk and Se-ri turn the corner and see Dan, Se-ri knows exactly who she is. Awk-ward. Dan studiously ignores Se-ri as she tells Jung-hyuk that she came to pick up her uncle's car, but Jung-hyuk offers to drive her home since it's late.
He explains that Se-ri is carrying out a mission with him, and that they won't see each other again after it's over. Se-ri backs him up and rambles a bit about being in Division 11, but Dan says she doesn't care, heh. Jung-hyuk sends Se-ri inside, promising to be back soon.
As they drive away, Dan notices that Jung-hyuk keeps checking the rearview mirror worriedly. She mentions that this is only the seventh time they've spent time with each other, and that only two of those times have been in the seven years since they were engaged. She says there's no love between them, and that she wants that before they get married.
Dan lets her mother know that Jung-hyuk will be dropping her off, so her mom parades around in front of her brother, Colonel Go, in inappropriately fancy outfits trying to decide what to wear. He tells her to just be polite, so she ends up choosing a hanbok, ha.
When they arrive, Jung-hyuk is anxious to get back to Se-ri, but Dan's mother insists he stay for dinner. She goes on and on about how the matchmakers are pestering her to let them set up Dan (Colonel Go: "I never heard about this…"), and Jung-hyuk nervously checks his watch.
Seung-joon is also thinking about Se-ri, sure that the woman he saw tonight looked just like her. Se-ri's brother Se-hyung had once set Se-ri and Seung-joon up on a blind date, where Se-ri had played her Picky Princess role to the hilt. She had made it clear there wouldn't be a second date, having pegged Seung-joon as a conman right away, and had told him to just scam some money from Se-hyung then get lost.
In the present, Se-ri gets excited every time she thinks she hears Jung-hyuk returning home, then laughs at herself for getting all worked up. Eventually the village wives show up with snacks and beer, wearing their most sympathetic faces for what they think is Se-ri's betrayal by Jung-hyuk. They've decided that Dan has no morals, and Se-ri teaches them a few South Korean swear words that apply to women, ha.
Young-ae, who's always thought highly of Jung-hyuk, tells Se-ri that she ought to break his neck for getting engaged to two women at the same time. The women start to talk about teaching Jung-hyuk a lesson, and even Man-bok, listening in from his bunker, grumbles that you can't judge a book by its cover, HAHA.
Young-ae says she's going to tell her husband to make sure Jung-hyuk isn't promoted, and Se-ri realizes she has to do something. She tells the ladies that Jung-hyuk and Dan's engagement was arranged by their parents, and that her relationship with Jung-hyuk is sort of a star-crossed Romeo and Juliet story.
After leaving Dan's home, Jung-hyuk goes to see his own parents (who have an ostrich instead of a guard dog, lol). Director Ri says that he wants Jung-hyuk to marry Dan within the year, and Jung-hyuk agrees, but he says he has a favor to ask in exchange.
When the ladies finally leave Jung-hyuk's place, Se-ri takes the opportunity to ask Young-ae again to put in a good word for Jung-hyuk with her husband. Wol-sook, who is sloppy-drunk, screams at Se-ri that boyfriends are better than husbands anyway, and she has to be carried home, hee.
It's morning when Jung-hyuk finally returns home, and he finds a suspiciously calm Se-ri waiting up for him. HAHA, she's lined up empty beer cans across the floor, and she tells him not to "cross the line" and there won't be a war.
Jung-hyuk explains that he's been setting up a way for her to get out of the country, and Se-ri's anger deflates. He says that she's going to become a reserve member of the international track team, travel with them to Europe, then "go missing" and make her way home to South Korea. Unfortunately, Man-bok is still listening to Jung-hyuk's house, and he hears every word of their plan.
Se-ri will need a passport, which means she has to get a North Korean hairstyle for her photo. All of the options are at least twenty years out of style, so Se-ri chooses the one that only involves embarrassingly huge waves. The ladies take her shopping for clothes, and she actually gets into it, but she realizes belatedly that she has no money.
They go to a pawn broker, and for a moment Se-ri considers pawning a jeweled necklace she's wearing. She decides against it and instead pawns her watch, expecting a lot for it since it's a limited edition. She's shocked to only get a few dollars for it, since the payment is based on the weight of the tiny leather band. She notices another limited edition watch for sale, and the pawn broker says that a man pawned it many years ago but never returned for it.
Man-bok reports Jung-hyuk and Se-ri's plans to smuggle her out of the country to Chul-kang, including the fact that they need to go to Pyongyang soon to get her a passport. He believes it might be a plan formed by Division 11, but Chul-kang knows now that Se-ri's not in Division 11.
Out of nowhere, Chul-kang mentions Jung-hyuk's brother, Moo-hyuk, and the fact that the watch he was wearing when he died went missing. He says that if that watch is ever found by Jung-hyuk, both of them will be in serious trouble.
When Jung-hyuk gets to the base for training, he notices that the ducklings are missing, and he's informed that they were all summoned to the State Security Department. Oh noooo.
Chul-kang confronts a very frightened Eun-dong and tells him that of the four of them, only the first who tells him the truth about Jung-hyuk will survive. But Eun-dong is smart — he says it's been a while since they were brought here, so Chul-kang must have already questioned the others, but the fact that he's still asking means he hasn't learned anything.
Furious, Chul-kang punches Eun-dong, but Jung-hyuk storms in and snarls at Chul-kang to ask him directly if there's something he wants to know. Chul-kang says he won't tell the truth, but Jung-hyuk retorts that only the person involved can tell the truth, so it's time for Chul-kang to go tell the truth about his own actions.
Just then, the senior colonel calls Chul-kang to ask why he's received an official request from the State Security Department, who want to speak to him and Chul-kang about the recent truck accident. HAHAHA whoops. Jung-hyuk leaves with Eun-dong, and when he runs into Man-bok in the hall, there's an awkward moment before they continue on their way.
Se-ri sees some kids bullying a little boy, yelling that he's the son of "the Rat." Se-ri tells them that bullying is cowardly and chases them home. She asks the boy (he's Woo-pil, Man-bok's son) why he let them bully him, and he says his dad told him to be good to his friends, so Se-ri clarifies that that doesn't apply to people who beat him up.
She tells Woo-pil to hit them if they hit him first, and he asks if that's what she did (he calls her "noona," utterly charming her). Se-ri says that she did, which made them stay away from her, but that it's better to be lonely than hurt.
Back in Seoul, Secretary Hong and Soo-chan visit a man who says he heard something strange on a walkie-talkie signal recently. He plays them the recording, and it's clearly Se-ri calling for help. They're thrilled to have proof that she's alive, and they ask the man for the audio file.
Se-joon's wife, Hye-ji, visits her mother-in-law in the hopes of garnering favor for her husband. Instead she manages to insult Se-ri's mother by saying that she'll be her daughter now that Se-ri is gone, and gets kicked out of the house.
Se-hyung is in China, chasing down a lead on Seung-joon. His people have caught Seung-joon's broker, Mr. Oh, and Se-hyung offers to pay him ten times what Seung-joon paid him to catch the swindler. Mr. Oh calls CEO Jeon, who agrees to help in exchange for a cut.
Jung-hyuk brings the battered and bruised ducklings home for ramyun. Se-ri apologizes to them and says she wants to give them all a gift, then solemnly flashes finger-hearts at them. HAHA, their faces. As Jung-hyuk walks them back to their barracks, they decide it must not mean romantic love like they assumed, and hee, Jung-hyuk looks so put out.
When he gets home, he just glares at Se-ri until she notices, then grumbles, "Do you have multiple hearts?" He peevishly says he's sleeping in his own bed tonight, then sits up late pouting like a toddler, ha.
At bedtime, Myung-sook tells Man-bok about Se-ri chasing away their son's bullies, and saying that it doesn't matter if his father is the Rat. She says supportively that Man-bok is only doing as he's ordered, but after they're all tucked in bed, Man-bok thinks about a day years ago when he was beaten up for getting a fellow soldier into trouble for selling drugs.
They had threatened to cut off his ears so he couldn't rat on anyone, but Moo-hyuk had shown up and chased the bullies away. Now, Man-bok lies in bed thinking about Moo-hyuk's kindness, and he sobs with grief.
Jung-hyuk and Se-ri take the train to Pyongyang the next day to have her photo taken for her passport. Coincidentally, Seung-joon and CEO Jeon are on the same train, because Seung-joon is bored and wants to visit a casino.
Seung-joon asks Jung-hyuk what will happen after she "disappears" in Europe. In flashback, we see that Jung-hyuk's father had told Jung-hyuk that he won't help him if the person he's smuggling out of the country gets into trouble, but Jung-hyuk tells Se-ri that nothing bad will happen to him.
The train has a power outage and stops right in the middle of the tracks, and to Se-ri's dismay, Jung-hyuk says it could take up to sixteen hours to repair. People begin running up to the train on foot, and Jung-hyuk explains that they're "hopping salespeople" — people who sell food, water, and other items to people who unexpectedly have to spend the night on the train.
After dark, Jung-hyuk sets up a little camp for himself and Se-ri, since there's no heat on the train and at least they can build a fire outside. He buys some blankets when Se-ri bats her eyelashes at him, and some corn to roast when she gets hungry.
He gets frustrated and calls her greedy when she hints broadly for some hot water to wash her face, so Se-ri pulls out her own money to buy it. She says she pawned her watch to buy herself some clothes, and she mentions the nice men's watch she saw at the pawn broker's stall.
Se-ri burns her fingers picking up a hot potato, so Jung-hyuk sighs and starts peeling it for her. She tells him he's a good man, and that he'll make a good husband and father one day. Jung-hyuk admits that he hasn't really thought about it because he gets disappointed when things don't go as he hopes.
He's thinking about giving up piano when his brother died, and though he doesn't say so, Se-ri says that she can tell that whatever happened broke his heart. She mentions the old proverb: "Sometimes the wrong train takes you to the right station," joking that she really took the wrong train this time and making Jung-hyuk laugh.
More seriously, Se-ri tells Jung-hyuk to think of the future even if things don't go as he wishes. She says that she hopes he's happy after she leaves, and that he arrives at the right station no matter which train he takes.
They finally get to Pyongyang in the morning, and Se-ri enjoys looking around at the unfamiliar city even if, as Jung-hyuk says, she looks like a "country bumpkin." After getting her passport photo taken, Se-ri suggests that she and Jung-hyuk take a picture together as a memento. He bursts her bubble by saying that they have no reason to remember each other.
As CEO Jeon checks himself and Seung-joon into their hotel, Seung-joon looks like he's getting suspicious of something. In their room, Seung-joon excuses himself to change for dinner, and CEO Jeon calls Mr. Oh to say that they're in Pyongyang and that Seung-joon doesn't suspect anything.
Suddenly, he finds Seung-joon holding a gun to his head. Seung-joon takes the phone and yells at Mr. Oh for turning on him, but Se-hyung gets on the line. He tells Seung-joon that he's found him, and that he's dead once he returns Se-hyung's money.
Seung-joon has gone down to the hotel lobby, and to his surprise, he sees Se-ri walking towards him. He asks Se-hyung how his sister is doing, but Se-hyung says she's dead. Seung-joon tells Se-hyung he'll give Se-ri his regards and hangs up, then he grabs Se-ri's hand and pulls her into an elevator.
Grinning, he says he may not die after all, as Se-ri just stammers in surprise. A hand stops the elevator door from closing — it's Jung-hyuk, who sees them still holding hands and advances on Seung-joon.