S Line Episode 1-2 Review
Director: Ahn Joo-young
Date Created: 2025-07-12 14:24
4.5
S Line Episode 1-2 Review: The new Korean drama adaptation of the popular webtoon by Little Bee, is already making global headlines, thanks to its bone-chilling premise and winning entry at the 2025 Cannes International Series Festival, as Best Music Award winner for Feature Film Competition. With just six episodes in total, the series kicked off with its first two on July 11, 2025, and has quickly become a talking point among drama fans. Penned and directed by Ahn Joo-young, the series features Lee Soo-hyuk as detective Han Ji-uk, Lee Da-hee as quirky schoolteacher Lee Gyu-jin, Oh My Girl’s Arin as enigmatic loner Sin Hyeon-hop, and Lee Eun-saem as troubled teenager Kang Seon-a.
At the centre of S Line Kdrama (S라인) is a disturbing enigma: red lines called “S Lines” that bind people who have had a sexual relationship with each other. The lines cannot be seen by everyone, but certain individuals do see them. The drama is a fantasy, psychological thriller, and social commentary in one, dark but introspective exploration of desire, shame, and secrets in contemporary society.
S Line Episode 1 Recap
S Line Kdrama Episode 1 is an atmosphere of haunted, chilling quiet as we meet Sin Hyeon-hop, a teenage girl who’s spent her entire life observing red lines hovering over the heads of other people. The lines, visible only to her since birth, foretell sexual encounters—and the higher the number of lines an individual possesses, the more “complicated” their past. As a child, Hyeon-hop attempted to rationalise what she was seeing, even sketching in the red lines into her books. Her mother, unable to cope with what was real, murdered her father. Now a recluse, Hyeon-hop wears black sunglasses, stays indoors and maintains all human contact at arm’s length, tormented by what she’s seeing.
She sees the world behind cardboard-covered windows in her one-room apartment. She sees one man standing in front of her apartment building with just one red line, a peculiar thing that catches her eye right away. Her new neighbour is normal and nice, but suspicion is heightened as Hyeon-hop watches over her bond with this one-line man through a new red thread.
Meanwhile, Detective Han Ji-uk is struggling at work and in his love life. He is like a Casanova as he is sleeping with his co-worker, who is going to be married and multiple other women as well and also taking care of his niece, Seon-a, because she’s getting bullied at school. Han’s not exactly the father figure type, but once he sees Seon-a with bruises all over her, he doesn’t care, although she refuses to speak to him.
At the same time, however, Han is working on an unusual murder case at the precinct, and Hyeon-hop is still stalking the single-line man from her apartment. Upon seeing him enter the new neighbour’s apartment and noticing a disturbance, her fear gets the better of her. She is scared but trying to do something; she takes a knife with her and exits her apartment—a huge step for someone who has lived in isolation for years. She passes out in terror on the sidewalk before she compels herself to break into the apartment, where she is attacked by the man in fighting gear.
Detective Han sees the red-string map on the wall of Hyeon-hop’s apartment, and, through her window, he can see the fight taking place across the way. He rushes over and shoots the assailant, saving the neighbour from being killed. When the man is on his deathbed, he mutters something about vanishing S Lines, and Hyeon-hop is left questioning whether or not the special glasses he was wearing enabled him to see them. She subsequently gets a mysterious message from someone who indicates that he can see what she can see—to open up her cage and look at what’s outside.
Also Read: 10 Best Quotes of Our Unwritten Seoul That Our Heart Will Never Forget
S Line Episode 2 Recap
S Line Kdrama Episode 2 shifts the focus to the school environment, where we see awkward teacher Lee Gyu-jin—her quirks include driving so slowly, she gets nudged by her students. One of her students is Detective Han’s niece Seon-a, who still struggles with bullying and trauma. After standing up to her bully, Seon-a is scolded by school administrators.
But as she is about to leave for home, she discovers a peculiar pair of glasses in her locker. The glasses are peculiar beyond recognition—when she tries them on at home, she can see something incredible: a red line hovering over her own head, and even more foreboding, a trail of dozens of red lines hovering over her uncle Han’s head.
Upon learning of the power of these glasses, Seon-a begins wearing them to school. She wonders how many of her classmates probably have red lines of their own, and if official counts of teenage sex are wildly too cautious. She sees the red line between the teacher and the student who has been bullying her, and also observes that her homeroom teacher Gyu-jin, has no lines whatsoever—more secrets. Hyeon-hop, after saving her neighbour, finally gets the feeling that the red line might not be that bad, as she thinks, so she finally decides to go to school and moves to class on that day, with furrowed eyebrows because of her strange, quiet nature.
Detective Han returns to the crime scene and sees a photo of Jeong Min, the murderer, wearing glasses that were not discovered in the evidence. He conjectures that the glasses are the cause of being able to perceive the S Lines. Detective Han interviews Gyu-jin at school and asks him if he knew anything about Jeong Min’s glasses-wearing habit.
As Seon-a catches her abuser, Hye-yeong, entering a hotel with a teacher and takes a clandestine photograph of the act. She blackmails the teacher afterwards with the photo for 20 million won—maybe to flee her violent life. When queried what she would do with the money, she merely said that she would lease an apartment of her own. Seon-a is warned about the risks of wearing the specs by Hyeon-hop, citing the sorry life of the former owner, but Seon-a is not heeding.
Soon, someone swipes the glasses, and Seon-a frames Hyeon-hop for it, and they start a vendetta with each other. But the real thief, Hye-yeong, is listening in on them. Seon-a returns to pick up the cash from the teacher, but discovers his wife has received the same accusatory photo. The teacher is driven into hysteria. Just when matters sort themselves out, Hyeon-hop shows up at school—only to see Seon-a tumbling off the rooftop. Her demise sees the episode end on a dramatic and tragic note.
S Line Episode 1-2 Review
S Line series is not just a thriller, it’s a risky foray into taboo subjects from an imaginative angle. The concept of the red line is an odd one, but it’s used to comment on human intimacy, loneliness, trauma, and humiliation in an innovative way. The series comes up with its own twisted logic and then challenges us to question our own assumptions about relationships and morals.
Episode 1 of S Line stands out for its paced, atmospheric construction and for the manner in which we find ourselves spending a great deal of time in Hyeon-hop’s viewpoint, seeing the world through her shut windows and black spectacles. Her trauma and terror are set up in frosty quiet, so the eventual action scene is that much more effective. The detective element introduces a touch of realism, making the supernatural premise more about personal interest and emotional need.
Episode 2 of S Line dares to put the spotlight on Seon-a and her teenage life as a high school student. How she learns to utilise the glasses so she can observe—and manipulate—the world around her is questionable from an ethical standpoint. She is a manipulative victim and victim, and that contradiction is dealt with perfectly. She dies tragically because we feel sorry for her suffering, even though we disapprove of what she does.
What makes this drama stand out is that it employs fantasy not as an escape but as a confrontation. The characters are not perfect, and within the world they live in, there is judgment and deception. The S Lines as a metaphor for secrets and the price of knowing too much. Visually and emotionally, the show makes its mark.
S Line Kdrama Review (Episode 1-2): Final Thoughts
Overall, with only two episodes, Korean drama S Line has set the bar high for dramas by being bold enough to blend thriller, fantasy, and social commentary. The dark story, full character arcs, and brutal visuals make it difficult not to keep an eye on it. And now that Seon-a is deceased and the mystery of the glasses is happening, it will be fun to see what the next episode brings us.
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