S Line: Story, Cast and Series Facts

Story and premise

Suddenly red lines appear above people's head. These red lines connect people who have had sex relations. Due to this, embarrassing or secret sides of people are revealed. People call these red lines "S Line."

Han Ji-Wook (Lee Soo-Hyuk) is a detective with an attractive appearance and free spirit. He chases after the truth of the S Line. Kyu-Jin (Lee Da-Hee) is a high school teacher with unique charm. Hyun-Hob (Arin) is a high school student. She has been able to see the red lines since she was born.

Series details

• Title: S Line
• Format: Scripted
• Language: Korean
• Genres: Drama, Fantasy, Thriller
• Premiere date: 2025-07-11
• Final broadcast date listed: 2025-07-25
• Status in TVmaze: Ended
• Web channel listed by TVmaze: wavve
• Network country: Korea, Republic of
• Typical episode runtime: 52 minutes
• TVMaze ID: 85537
• IMDb ID: tt36056620
• TVDB ID: 462241

Cast and credited roles

• Lee Soo Hyuk — Han Ji Wook
• Lee Da Hee — Kyu Jin
• Arin — Hyeon Hob

Seasons in the TVmaze catalogue

• Season 1: premiered 2025-07-11; final listed air date 2025-07-25; episode order: 6.

Source and licence

Adapted from S Line on TVmaze. The synopsis is reproduced as plain text; catalogue facts, cast and season records are selected and reformatted. This adapted text is available under CC BY-SA 4.0, following the TVmaze API licence. Network and web-channel credits identify the service listed in this source; they do not establish current streaming availability.