South Korea / SEASON

Season 1

6 listed episodes · First aired July 11, 2025

Season overview

Hyeon-heup has been able to see the mysterious 'S lines' since birth, a secret only she could perceive. But when special glasses allow others to see it too, long-buried secrets and hidden connections surface, pulling her into a web of desire, betrayal, and dangerous truths in this haunting thriller.

EPISODE GUIDE

Episodes

Full guide ↗
E1The Girl With The Sunglasses

Hyun-heup, a girl who was born with the ability to see the S-line that indicates sexual relations. Because of this ability, Hyun-heup's family faces tragedy, and Hyun-heup becomes a reclusive loner for a long time. Then…

E2The Animal Kingdom

Hyun-heup goes to Bangju High School after receiving a mysterious text message. There, he reunites with Seon-ah, a middle school classmate and Ji-wook's niece. However, Seon-ah is a victim of bullying from bullies. One …

E3A Fall Into Darkness

Seon-ah falls from the rooftop and falls into a coma. Ji-wook cries out in self-reproach and anger, and cooperates with Hyun-heup to find the culprit. Meanwhile, Jung-woo, an English teacher at Bangju High School, witne…

E4Miseong Motel

Ji-wook, who was continuing the investigation to find the culprit of the Seon-ah incident, hears about the S-line from Hyun-heup, but doesn't believe it. Meanwhile, Bang Ju-goo, an employee who lives in a goshiwon and d…

E5The Glasses

Ji -wook, who finally discovered glasses in the bloody bathtub of aesthetic, admits that the words of Hyun -suk were true. Use the power of glasses to start an investigation into sexual violence in the runway. And I thi…

E6Chaos on the Horizon

Ji -wook finds out the truth about Sun -ah's S -line through glasses. Meanwhile, Hyun -suk, ahead of his 18 -year -old birthday, makes a big decision and meets the Jun -sun, which leads to an unknown confusion.