Dan confronts Jung-hyuk with the article detailing Se-ri's accident, demanding to know why he's willingly harboring a woman from the South – an act that could cost him his life.
Having already lost Moo-hyuk, Jung-hyuk has experienced the grief that comes with failing to protect someone he cares about. Death would've been better, so he's going to send Se-ri home no matter what.
Seung-joon provokes Se-ri with a similar point of concern: does she not care if Jung-hyuk gets hurt because of her? Not one to be threatened, she remains unaffected but Seung-joon asserts that he's just stating facts.
He steadies his gaze to meet Se-ri at eye level, drawling that if she's thankful, sorry, or perhaps even likes Jung-hyuk, then she should disappear before anything worse happens. Seung-joon warns that she's been lucky thus far, but anyone who's found helping her will get in trouble.
In a thinly veiled threat, Dan vows that she'll do anything to keep her fiancé safe, but Jung-hyuk wordlessly walks away despite Dan's warning to not do anything he'll regret. He gets an enthusiastic send-off from the doctors as he drives off in a borrowed ambulance. The GPS leads him off the beaten path, but he continues on despite looking unwell.
In voice-over, Seung-joon tells Se-ri that the moment she got involved with Jung-hyuk, his life must've begun to fall apart. He guesses that Jung-hyuk's following a path that he's never been on before. Quite literally, Jung-hyuk takes an unfamiliar road that leads him to the edge of a cliff, unsuccessful in his search for Se-ri.
Meanwhile, Dan purposefully approaches a phone booth, hesitating as she eyes the State Security Department's hotline number.
The ducklings visit their captain at the hospital the next day, where Kwang-bum presents Jung-hyuk with his fixed phone. A call from Pyongyang comes through and Jung-hyuk answers immediately, thinking it's Se-ri.
It's actually a courtesy call from Seung-joon to report that Se-ri's safe. He advises Jung-hyuk not to look for her and hangs up abruptly. This prompts Chi-soo to confidently spin a tale: now that Se-ri's reunited with her "boyfriend from the South," she wants to forget about them.
Jung-hyuk snaps that they're not dating and have already broken off their engagement. However, the fact that Seung-joon was Se-ri's fiancé is news to the ducklings and only fuels Chi-soo's story. Jung-hyuk gets increasingly heated and yells at Chi-soo, but plays it off as if he's just chastising him for his bad-mouthing habits, haha.
Min-ji barges into their room to complain about the noise, but changes her tune when she realizes that Jung-hyuk is Se-ri's "ultimate bias," agreeing that he's a "babe magnet." Joo-mok proudly translates that Jung-hyuk is Se-ri's absolute favorite (cue the finger hearts) and that she's fallen for his irresistible charms. Absolutely elated, Jung-hyuk fools nobody when he denies that he's smiling.
It's moving day for Dan, whose mother calls her out for looking sad. Colonel Go animatedly shares a story about his wife, who'd gotten cold feet before their wedding because she liked someone else. He let her go but she eventually returned to him. When Dan leaves to get some fresh air, her mom wonders if something's going on.
At the villa, CEO Jeon freezes when he spots Se-ri and plays along when Seung-joon introduces him as Butler Jeon. Outside, he chides Seung-joon for breaking his promise with Chul-kang but the mention of receiving full commission with him out of the picture is enough for CEO Jeon to be on board.
Their first order of business is to separate Se-ri from Jung-hyuk, who's bound to send her back to South Korea. As if on cue, Dan calls Seung-joon and they meet for coffee. She's here to confirm that he knows Se-ri, that she's not from Division 11, and snuck in from the South.
He admits that he knows her well but Dan doesn't care that Se-ri didn't sneak in – it's what she'll say when she reports her. He points out that Jung-hyuk will be affected, but Dan coolly claims indifference.
Seung-joon suggests collaborating, sharing that he has a plan. Dan leaves, but Seung-joon knowingly begins to count down and sure enough, she's back in her seat by the time he gets to "one," hah.
Newly discharged, Jung-hyuk visits an electrical substation and meets with an old acquaintance. The acquaintance deduces that the hidden villa Jung-hyuk's looking for is likely connected to a special power line that leads into the woods. Jung-hyuk heads to the forest and follows the power line on foot.
Lying in bed, Se-ri suddenly recalls that hotels in the North are bugged and perfectly re-enacts the scene of Jung-hyuk debugging a room. She shows the devices to Seung-joon and CEO Jeon, who look uncomfortable when she warns them to be careful.
Se-ri declares a meeting to plan her return to the South. When CEO Jeon suggests the "confidential" method of boat-to-boat, Se-ri knowledgably explains what it is to a confused Seung-joon, but dismisses the idea due to the sea control order.
Seung-joon doesn't intend on having Se-ri attempt anything dangerous though; he plans to have her marry Alberto Gu (his British identity) and fly home in business class. Despite knowing that this isn't the real plan, CEO Jeon lets out an impressed "oooooh," while Se-ri asks if "Alberto" is crazy.
Dan's mother shows up at Jung-hyuk's house, but only finds the ducklings. She serves food and soju, clearly fishing for information, which Chi-soo feeds to her without a second thought. Kwang-bum gives a verbal warning, but Dan's mom zeroes in on her target and convinces Chi-soo to drink the night away.
It's a snowy Christmas Eve, and Seung-joon has prepared clams just the way Se-ri likes it, paired with her favorite wine. Rather than be excited, she reminisces her simpler (and happier) clam-and-soju meal with the boys.
Seung-joon takes this opportunity to present Se-ri with a ring. He wants to get married for real – Se-ri may have feelings for Jung-hyuk now, but he claims that they're fake and only developed because of her situation. He slips the ring onto her finger and asks Se-ri to marry him.
Jung-hyuk approaches the villa, taking the guards out one-by-one despite his injuries. Se-ri spots him through the window, recoiling each time he's hit. She's about to head out to help, but is shaken to learn that Jung-hyuk will face consequences (a.k.a. death) upon her successful return to the South. Dan has discovered her identity and will report her, but if Se-ri leaves Jung-hyuk, then everybody can return to their rightful places.
When our leads reunite, the first thing Jung-hyuk asks is whether she's hurt. Holding back tears, she nags him for not taking care of himself. What's he doing out here in the cold when he should be resting?
Jung-hyuk answers plainly, "I came for you. I figured you'd be waiting for me." She puts on a façade and fibs that she can't trust him anymore because his ideas keep failing, then reveals her plan to marry Seung-joon. He watches Se-ri intently as she goes on a spiel about how much she wants to leave this place and for him to leave her alone.
He gently takes her by the shoulders to ask if she means it. She insists she does, but her face indicates otherwise. "I get it, so don't cry," he gently wipes away her tears, and I'm sure he knows she's putting on a front. They look deeply into each other's eyes, seemingly communicating their feelings before he turns and leaves.
Seung-joon gives Se-ri some space, and she weeps for Jung-hyuk. The snowfall gets heavier and she worries that he'll freeze, so she takes off in Seung-joon's car. When Se-ri finds Jung-hyuk, she claims she's only giving him a ride home. When she looks up at him with her sad eyes, he pulls her into an embrace that they both desperately needed.
In the car, she insists that they'll go their separate ways once he's home, but there's no more gas in the tank. They make their way to a nearby school, where they'll be able to build a fire and stay warm during the storm.
Chul-kang meets with the Military Director of the Central Committee in secret. If Director Ri is the setting sun, then the military director is the rising one who's waiting for the right moment to step into power. Chul-kang explains the situation regarding Jung-hyuk and his lady-friend from the South.
He sneakily plants the idea that even Director Ri can't survive if they turn Se-ri into a South Korean spy. The military director wants Se-ri brought to him alive before he makes any career-altering moves.
Man-bok reports that Jung-hyuk's not at home, and the hospital director is held at gunpoint as he shows Chul-kang the surveillance footage that reveals Se-ri getting into Seung-joon's car. Meanwhile, Seung-joon calls Dan and says that it's her turn to make a move.
Jung-hyuk and Se-ri warm up by the fire inside the school. He disapproves of her fake marriage to Seung-joon, and she shares her worries that her existence will shatter his life as he knows it. Jung-hyuk denies that Dan is his first love when Se-ri asks, but remains silent when she probes to learn who it is. She tsks that she should've figured that he's the type to have been single since birth, and they chuckle that he's able to tell that it's an insult.
Under the same snowy sky, Myung-sook finds Man-bok drinking alone, accurately guessing that he's worried about Jung-hyuk. She reminds him that it's just his duty to the country, and it's not Man-bok's fault even if something happens to the captain.
Man-bok reveals that he's responsible for Moo-hyuk's death, and that Jung-hyuk's his brother. If something happens to him too, Man-bok isn't sure he can live with himself. He cries that it's cruel that he must let the ones who treat him well die, while staying loyal to those who don't.
Se-ri finds Jung-hyuk asleep in an upright position and gently guides his head onto her shoulder. She slips her hand into his as he sleeps, dreaming of Moo-hyuk once again. We're brought back to the moment when Moo-hyuk sent Jung-hyuk off prior to studying abroad. Jung-hyuk had gifted Moo-hyuk with the watch, and the brothers fussed over one another to stay safe.
When Moo-hyuk disappears from his dream, Jung-hyuk wakes up in a sweat. As the storm has stopped and the sun is out, Se-ri suggests that they either head home or to a hospital to deal with his fever.
Dan pays Director Ri a visit, but we don't get to hear what she says. Seung-joon and CEO Jeon wait for their backup car to chase after Se-ri with, but they get an angry Chul-kang storming in with a search team instead.
Chul-kang attacks Seung-joon and holds him at gunpoint, "Listen up, you South Korean scaredy-cat. I'm not interested in money." He needed the money to get to the things he truly wanted, like the power to kill whoever, wherever. Jeez, could you get more stereotypically evil? Chul-kang demands to know where Se-ri is.
The couple hitched a ride and make their way home, where the boys berate a hungover Chi-soo for spilling the beans to Dan's mother. Even the young Eun-dong is furious, wondering what will happen to their captain and Se-ri.
Chi-soo blames the mother for torturing him with alcohol, but Joo-mok calls him out for being so enthusiastic that he even made her write everything down. Chi-soo then claims that he was targeted for being highest ranked and with the most valuable information. Kyung-bum, "You probably looked the easiest among us." Hah, he's not wrong!
In a round-about way, Chi-soo asks them to keep his blabbering a secret from Jung-hyuk, but everyone shakes their heads in disappointment.
Dan finds her mom curing a hangover as well. Sensing that something was up with Jung-hyuk, her mother had gone to talk to him. She'd made "the loudmouth" spill something extremely shocking and Dan, in anticipation, asks what she heard… but mom got too wasted and forgot everything. HAHAHA.
Mom finds the written notes on her arm (swallow from the South, two out of three meals have meat dishes, hair smells like flowers), but they're not helpful. Dan asks why she's so curious anyway, and mom answers seriously that she wants to know if her daughter is happy and if her fiancé loves her. Aww. Dan promises to marry him no matter what and live happily ever after.
Now at home, Jung-hyuk takes some medicine and declines heading to the hospital. Se-ri promises not to leave yet since he's sick and it's Christmas Day. Man-bok's extremely relieved and happy to hear that they're both fine, but receives another call from Chul-kang asking if the two are home. This time, he lies that they aren't.
It's the start of winter vacation for the kids, and the ladies of the village gather around to pick up their children. Before heading home, the kids are told to show their exam results. Wol-sook's son cheekily says, "Mom, you'll be very embarrassed. Will it be okay?" which leads to an angry outburst.
Relaxed, Young-ae shares that she recently hired a tutor from the top university to tutor her own son, Nam-shik. The mothers of the village are impressed, and Young-ae is ecstatic to hear that Nam-shik scored 100 points.
The problem is… his 100 points are a sum total of four different exams, HAH! I love these kids. Everybody disperses quickly and Young-ae runs after Nam-shik with a stick, stopping short when she sees Se-ri.
Over tea, Se-ri explains to Young-ae and the others that she's just stopping by, acting unaffected when Ok-geum shares all the details of the furniture that Dan moved into the newlywed apartment. She wants to get them a present to thank them for everything, pulling out her shiny new ring when they mention that she's broke.
Se-ri's back at the pawnshop singing praises about her ring, backed up by the other ladies. To everyone's shock, she starts the bidding at 5,000,000 won, which is way more cash than he has in the register. He refuses to take it, since it's an item nobody else will buy.
Wol-sook whispers something into his ear, asking him to be more flexible. Whatever she said worked, and he agrees to exchange every item he owns with the ring. The ladies happily strut through the market with their loot, which even includes a baby goat!
When asked what she'd said to him, Wol-sook lies that it was nothing. In reality, she'd told the pawnbroker that Se-ri was dumped and not in her right mind. None the wiser, Se-ri happily clutches the watch that used to belong to Moo-hyuk.
Soo-chan and Secretary Hong discover that Se-ri's brother and sister-in-law testified that the voice recording wasn't of Se-ri. Since Se-ri's already been announced dead, the police aren't inclined to investigate further.
Secretary Hong later explains that the siblings aren't close and that they value stocks over sibling bonds. Their only hope is Chairman Yoon, but it's not easy to meet him. They end up staking out at a VIP parking garage, but Soo-chan reacts too quickly and ends up revealing himself to Se-hyung.
When Chairman Yoon actually arrives, Se-hyung blocks their attempts to share information about Se-ri and leads his father inside to take the elevator. Despite being held down by guards, the two make a huge ruckus yelling that "Se-ri's alive!" in a last-ditch attempt to get the chairman's attention, and it works.
Jung-hyuk wakes up from his nap and smiles to see a makeshift Christmas tree with handmade paper ornaments in the living room. He receives a call from an unknown number, and it's Se-ri. The shakiness in her voice makes me nervous as she tells Jung-hyuk that she's leaving earlier than expected with Seung-joon.
He runs outside and insists on looking for her no matter how far away she is, because they need their last goodbyes. As expected, Se-ri's sitting in the back of a truck with a gun pointed at her. She cries to hear how anxious Jung-hyuk sounds and she tells him to be safe, have a good marriage, and live a long and happy life by forgetting her.
The kidnappers indicate that it's time to wrap it up. Jung-hyuk begs her not to hang up as he runs through a forest looking for her. He stops to listen to her final words, "Ri Jung-hyuk, I love you," and the sound of a gunshot resonates through the air. He looks absolutely lost, tears streaming down his face.