S Line isn’t here to play it safe. S Line Episode 2 dives deeper into the twisted red lines that expose people’s sexual connections — and things start getting real dark, real fast. With secrets spoiling left and right, school drama getting messier, and a death that changes everything, this episode doesn’t slow down for a second.
S Line Episode 2 Review: Lee Eun Saem
S Line Episode 2 Recap
We start off at school, where we meet the old teacher Kyu Jin, who either drives super slow or her car’s just that bad. Detective Han’s niece, Seon-A, is also a student here. She’s already questioning how many students are really sexually active — because the numbers seem way too low. Turns out, even she has a red line.
S Line Episode 2 Review: lee da hee
At home, Hyun Heup is settling in, while back at school, Seon-A nearly gets into a fight with her bully, but Kyu Jin stops them. Things get interesting when Seon-A finds a random pair of glasses in her locker. When she wears them, she starts seeing red lines floating above people’s heads, even above her own. These glasses show who’s been with whom — and it’s wild. She notices a scandalous link between a teacher and a student, and laughs when her own homeroom teacher, Kyu Jin, has no lines at all. But things take a strange turn when Hyun Heup suddenly transfers into her class.
S Line Episode 2 Review: Lee Soo Hyuk
Detective Ji-Wook is still suspicious about the murder case. He revisits the suspect’s apartment and finds a wall full of red strings, but something feels off. When he checks old photos, he notices the suspect wore glasses — but they’re missing from the evidence box. That leads him straight to the school and to Kyu Jin. Meanwhile, Seon-A continues using the glasses. She catches her bully, Hye-yeong, sneaking into a hotel with a teacher and snaps a photo. Then she blackmails the teacher, asking for 20 million won in exchange for keeping quiet. Hye-yeong cooly replies that the teacher’s the one who’ll get screwed, not her.
S Line Episode 2 Review: Lee Eun Saem
While all this is happening, Hyun Heup tells Seon-A that she can see the red lines too. She warns her that the last person who wore those glasses died — but Seon A brushes it off. She’s too caught up in the money and dreams of finally escaping her life. The teacher agrees to the blackmail, and Seon-A heads to collect the cash. But things go south quickly. Hye-yeong overhears everything and steals the glasses.
Seon-A wrongly accuses Hyun Heup of taking them. And just when the teacher thinks he can escape, his wife gets the same damning photo. He’s done for. In a heartbreaking twist, Seon-A falls from the rooftop right as Hyun Heup reaches her. Just like that, she’s gone.
S Line Episode 2 Review
Wow, this episode took a sharp turn. What started as a mystery with a cool sci-fi twist now feels more like a psychological thriller. The red lines aren’t just secrets— they’re dangerous. And the glasses? They might be cursed. The moment Seon-A fell was genuinely shocking. She was flawed, sure, but also just a teenager dealing with trauma and trying to take control of her life. Her story ended way too soon.
S Line Episode 2 Review: A Rin
Detective Ji-Wook’s character just got a whole lot more depth now that his niece is dead. This won’t just be another case for him — it’s personal. And that’s going to change everything. Kyu Jin is still a question mark. No lines at all? That’s either super innocent or super suspicious. And Hyun Heup is clearly not just a regular transfer student. Her reappearance, her connection to the glasses, and the mysterious text she got? All of it screams there’s more going on.
Final Thoughts
S Line is not your typical K-drama. It’s messy in the best way — fast-paced, full of twists, and it’s not afraid to go dark. With only six episodes total, the writers are wasting no time. Episode 2 crammed in so much drama, tension, and emotional weight that it honestly felt like a season finale.
The red lines might look pretty, but in this show, they represent something twisted. And now that Seon-A’s gone, we know the stakes are real. There’s a lot to unpack here: Who left the glasses in her locker? Why do they keep ending up in the hands of students? And who’s pulling the strings behind the scenes? One thing’s for sure, Detective Ji-Wook is going to dig deep now.
Also Read: All Review of S line