Jung-hyuk travels with Se-ri to meet the ship that's supposed to take her home, but before they can make the switch, the North Korean coast guard boards their boat and they're forced to hide in the hold. The new coast guard chief refuses to be bribed and orders the hold opened, and when he does, he sees Jung-hyuk and Se-ri employing the (supposedly) South Korean method of getting out of trouble — kissing.
Jung-hyuk shows the chief his credentials and explains that he was just taking his fiancee out for some night fishing (and a little pre-wedding get-to-know-you fun, according to Se-ri, hee). It works, and the chief lets them off the hook. But he tells them to head back to shore immediately, making Se-ri miss her chance to go home.
She's furious, but she decides to stay positive and just think of herself as temporarily lost. She tries to make Jung-hyuk promise to get her home within a week, but he says a "sea control order" has been issued and won't be lifted for around two weeks. Se-ri snaps that she just wants to be comforted, pointing out that Jung-hyuk has no problem lying when it gets him out of a scrape like claiming her as his fiancee or kissing her.
Poor Jung-hyuk stammers that she told him to do something, and he's flustered when she says it wasn't much of a kiss, ha. He's completely defeated by Se-ri's illogical logic, but he still refuses to make promises he can't keep.
Before dawn, Jung-hyuk hears his gate slam, and when he checks the living room, Se-ri is gone. She takes her paragliding equipment (the ducklings salvaged it previously) and hikes to the top of a mountain, intending to try and paraglide home.
Before she launches, Jung-hyuk catches up to her. He tells Se-ri that she landed here because there was a natural disaster, but it's a clear morning so she'll be seen and caught. He belatedly realizes that her walkie-talkie is on, just as Chul-kang arrives at the State Security Department and is informed that a suspicious transmission has been pinpointed.
Knowing that it will only take a few minutes for the authorities to arrive, Se-ri tells Jung-hyuk to stay here while she goes down and turns herself in. Jung-hyuk points out that he'll be in trouble anyway since they think he's her fiance, so he looks for another way out. He can see the military vehicles approaching, so he grabs Se-ri tightly and throws them both off the edge of the mountain.
Se-ri's parachute catches, and they gently float together through the air. Se-ri apologizes for taking her frustration out on Jung-hyuk earlier, and thanks him for everything he's done for her. By the time Chul-kang arrives at the mountaintop, they're long gone.
Chul-kang goes to his office and calls Man-bok in to ask what he knows. Man-bok hasn't heard anything strange, but Chul-kang still feels that something is off with Jung-hyuk and Se-ri, and he gives Man-bok some money to buy extra food for his son to entice him to keep spying on Jung-hyuk.
Man-bok goes to buy meat from the butcher in the marketplace, and while he's waiting, he overhears Jung-hyuk arranging to order coffee beans from the vendor at the next stall. Man-bok's wallet is stolen as he's paying, and Jung-hyuk begins to chase the thief while everyone else is still processing what happened. Unfortunately, the thief leads Jung-hyuk right to the local gang's hideout, and Jung-hyuk finds himself fighting the entire gang alone.
He does a pretty good job, and even pins the gang leader to the ground. He doesn't see another gang member sneaking up behind him, but luckily, Man-bok arrives and knocks the gang member out. They get out of there, and as Jung-hyuk walks away, Man-bok pulls a small piece of paper from his wallet.
The ducklings sit at Jung-hyuk's house with Se-ri, who's still so upset about missing her boat that she stuffs her face with rice crust and sugar, complaining that back home she's infamous for eating like a bird. She cheers up when Joo-mok tells her that Jung-hyuk asked them to protect her, taking it as a sign that he likes her. Chi-soo says it's because she's a troublemaker, so Se-ri asks for her products back, but Chi-soo refuses ("My head has never been so fragrant!").
Wol-sook comes to tell Se-ri that today is Young-ae's birthday (the wife of the senior colonel, and thus the unofficial leader of the village women). She's told to show up later for gift inspection, but Se-ri says that she doesn't go to other people's birthday parties and shuts the gate on them, ha.
The director of the Trial Bureau, who threatened Jung-hyuk before learning whose son he is, visits Chul-kang and nervously wonders if he should apologize to Jung-hyuk for that day. Chul-kang says that Jung-hyuk claims to have a fiancee who's in Division 11, and requests a meeting with the director's cousin in Pyongyang about the matter.
Se-ri is worried about how she'll get home, especially when she finds out that not only is Jung-hyuk not very highly-ranked, but that the more senior officers don't like him. Anxious to get rid of her, Chi-soo tells her about the Preferential Star, an award that offers a chance to get promoted when it's not promotion season.
The senior colonel gives out the award, so Se-ri shows up at Young-ae's birthday party after all. She's just in time to see Myung-sook (Man-bok's wife) being ridiculed for the frumpy handmade dress she's brought as a gift. Se-ri makes a few adjustments to the dress and describes it as the hottest worldwide trend, winning over both Young-ae and Myung-sook.
Meanwhile, Jung-hyuk and Kwang-bum drive to the Engineer Repair Unit to look for signs of a secret military truck unit. On the way, Jung-hyuk hears that Se-ri is trying to get him a Preferential Star and he simpers the same way she did about the ducklings guarding her… until he learns that it's because she sees him as low-ranked, and he huffs indignantly.
Naturally, the soldier in charge of the Repair Unit doesn't want to let Jung-hyuk in, so Kwang-bum stalls him (for a pretty boy, he can be damn scary) while Jung-hyuk looks around. Jung-hyuk notices blueprints and strange parts being made that match the odd armor on the front of the Kamaz trucks involved in the accidents, and he even swipes a small piece of dark metal before he and Kwang-bum leave.
By the time the birthday party is over, Se-ri is calling Young-ae "unni" (she's told the wives that her name is Sam-sook), and she convinces Young-ae to put in a good word for Jung-hyuk with her husband. Jung-hyuk rides by on his bike and hears them talking, so he backs up and rides past a few more times until Se-ri sees him (and almost falls off his bike when she does, PFFT).
He denies that he was waiting for her, but Se-ri isn't fooled for one second. Awww, he's even padded the bike's bar, and Se-ri guesses it's for her to ride on. Jung-hyuk gives her a ride home, fussing at her gently for planning to walk home in the dark. They're so darn cute.
The ducklings are still at Jung-hyuk's place when they arrive, and they tell Se-ri that Jung-hyuk bought clams and arranged for them to return to the barracks late tonight. They cook the clams by pouring alcohol on them and setting them on fire, and Joo-mok teaches her how to eat the clams then drink soju from the shells. As the evening goes on, Jung-hyuk sneaks glances at Se-ri, and he smiles at how pretty and relaxed she looks.
Back in Seoul, Se-ri's family gets together for a meal, and Chairman Yoon announces that he's giving Se-hyung the company. Se-joon and Hye-ji loudly object, and the brothers start tattling on each other. Se-joon reveals that when Se-ri was named successor, Se-hyung wanted to disclose to the press that she's actually Chairman Yoon's illegitimate daughter.
Se-hyung retorts that at least he still sees Se-ri as family, and wasn't glad she might be dead like Se-joon. Se-joon yells that their mother wanted to abandon Se-ri when Chairman Yoon brought her home, and their mother's had enough. She remembers Se-ri as a child, standing by the ocean and counting, and she says that they don't know what happened to Se-ri, so it's too soon to look for a replacement.
A very drunk Se-ri and Chi-soo play a word game, while Man-bok plays along as he listens from his bunker. Awww, he almost seems jealous of all the fun they're having.
In the morning, Jung-hyuk hand-roasts the coffee beans he managed to procure, and uses an ancient pour-over coffee making set to make a cup for Se-ri. She wakes up in his bed to the smell of freshly-brewed coffee (I'm so jealous), and Jung-hyuk is adorably pleased when Se-ri proclaims it perfect. He gets ready to leave, and Se-ri pretends to pull a little finger-heart out of her pocket for him.
He gathers Chi-soo and Joo-mok to ponder over what the gesture means, and naturally, only Joo-mok knows that it's a heart. He explains that the heart means love, and that a finger-heart means the person likes you. Jung-hyuk looks horrified that Se-ri may have taken his kiss seriously and developed feelings for him, and he's forced to confess that he already has a real fiancee.
In Pyongyang, Dan visits her family's department store with her mother, who fusses at her for having gotten too thin while studying in Russia. Dan explains that she has to be thin in order to be globally stylish. She chooses an outfit to wear when she sees Jung-hyuk for the first time in years, though her mother thinks it's too flashy.
Her mother's frenemy shows up to offer insincere flattery to Dan, and to humble-brag that her own daughter is now married and pregnant with her second child. Dan leaves to go see her old "friend," and the frenemy tells Dan's mother that apparently Jung-hyuk volunteered for the DMZ posting to avoid getting married.
Se-ri goes with Young-ae and Wol-sook to the market, where the vendor who sells South Korean beauty products offers them one of Se-ri's company's skincare products. Se-ri is overjoyed that her product is so popular it's even sold on the black market, and when the vendor doesn't seem to know much about it, she does a whole presentation on it for her new friends.
Insurance agent Soo-chan continues to dig up examples of people who have survived paragliding accidents, terrified that he'll have to pay out the huge policy Se-ri bought for herself. He and Secretary Hong run into Se-hyung and Sang-ah at the Se-ri's Choice offices, and Secretary Hong admits that he's been wondering if Se-ri's comment that she's about to go somewhere "high up" meant that she was planning to defect to the North. Se-hyung warns Soo-chan to stop spreading groundless rumors that Se-ri might still be alive.
CEO Jeon takes Seung-joon hunting, and when Seung-joon mentions that he hunted a lot in South Korea, Manager Oh fusses at him for mentioning where he's from. Seung-joon tells CEO Jeon not to nag him, but CEO Jeon argues that a lot of people will go down if their arrangement is discovered.
Dan locates a taxi to take her to see Jung-hyuk, but the driver (excuse me, I'm dying here, lol) says it's too far. Dan keeps offering him more money until he accepts, and soon they're off to the village.
On the way, the cabbie sings folks songs enthusiastically along with the radio (I can't, I just can't), so Dan put in her earbuds to listen to some classical piano music. She takes out a picture of herself and Jung-hyuk – she's looking at Jung-hyuk, but he's smiling at whoever is taking the picture.
On a remote dirt road, the taxi's engine stops, so the driver leaves Dan in the car to hoof it to the nearest village (taking the key with him, LOL). While she's waiting, Seung-joon drives by after finishing his hunting excursion, and he stops to offer her a ride. He tries his best flirting moves on her and gets soundly rejected, to CEO Jeon's great amusement.
Chul-kang gets a call from his contact, who says that he looked into it, and there's no woman of Se-ri's age and description in Division 11. In fact, there's currently only one woman in Division 11, and the contact knows her personally.
After dark, the market gets crowded, and Se-ri is separated from her friends. Wol-sook runs to Jung-hyuk's house and tells him that they lost Se-ri, and he goes into instant panic mode. He rushes to the marketplace, which the women find quite romantic.
Alone and scared, Se-ri stands in the busy marketplace, frozen and unsure what to do next. Something about the situation makes her remember being a child and standing by the ocean, counting to herself.
She counts again, and suddenly she sees a light in the middle of the crowd. She moves towards the light, and as she gets closer, she sees that it's Jung-hyuk holding up a candle. He looks so relieved to have found her, and when he says shyly that it's a scented candle this time, Se-ri smiles.