Teach You a Lesson K-Drama Cast and Characters Guide - Netflix Tudum

  • Who’s Who

    Meet the Team Schooling Bullies in Teach You a Lesson

    Juvenile Justice’s Kim Moo-yul and Lee Sung-min reunite to knock sense into violent students in this new K-drama.

    By Natalie Morin
    June 11, 2026

When schools don’t do enough to keep their toughest bullies in line, a different kind of teacher has to step up to help. Enter the Educational Rights Protection Bureau (ERPB), a fictional government agency at the heart of the new action-packed K-drama Teach You a Lesson. The bureau was created to protect victims of bullying and restore order in schools whenever anyone — students, teachers, or even parents — goes too far.

The situations in Teach You a Lesson aren’t basic schoolyard taunts or stolen lunch money — they include serious psychological and physical abuse with devastating consequences. Therefore, the ERPB requires a formidable team ready to whip these schools into shape (like, literally). Actors Kim Moo-yul and Lee Sung-min and director Hong Jong-chan reunite for this series after working together on Juvenile Justice (2022). ERPB founder Choi Gang-seok (Lee) and inspector Na Hwa-jin (Kim) apply unflinching ferocity to their pursuit of peace.

Below, meet the squad at the heart of the bureau (including a few ex-military), who’ll stop at nothing to protect students’ rights and restore justice in schools throughout Seoul. 

A gentleman in an all-black suit smiles with ease while a group of students look at him with anticipation.

Kim Moo-yul

as Na Hwa-jin
About the Character

Recruited after serving in a highly secretive, specialized sector of the military, Na Hwa-jin now works as an inspector of the ERPB. Armed with an unshakeable ease and a serious punch, Hwa-jin is the agency’s most valuable asset, restoring order in schools and bringing justice to victims of bullying.

Previously In

Eungyo

Watch them on Netflix
Juvenile Justice
Watch
Follow Kim Moo-yul

A gentleman in glasses and a suit holds up a clear zipped bag filled with pills while addressing a group reporters at a press conference.A gentleman in glasses and a suit holds up a clear zipped bag filled with pills while addressing a group reporters at a press conference.

Lee Sung-min

as Choi Gang-seok
About the Character

As the minister of education and the founder of the ERPB, Gang-seok employs an exceptionally skilled team of special agents to protect students, and is fiercely committed to the cause.

Previously In

No Other Choice

Watch them on Netflix
Juvenile Justice
Watch
Misaeng
Watch

A woman in green jacket looks off into the distance while a man grabs her by the arm as she attempts to break away.

Jin Ki-joo

as Im Han-rim
About the Character

Another former military operative, Han-rim is an ERPB inspector who takes pleasure in her role. To keep bullies in line, she uses any intimidation techniques she deems appropriate.

Previously In

Undercover High School

Watch them on Netflix
Misty
Watch
Follow Jin Ki-joo

A handsome gentleman lies on the ground with a menacing smile as someone stands over him.

Pyo Ji-hoon

as Bong Geun-dae
About the Character

The ERPB’s deputy director, Geun-dae, is more tech whiz than muscle, so he’s often tasked with going undercover for the bureau. 

Previously In

Encounter

Watch them on Netflix
Hotel Del Luna
Watch
Follow Pyo Ji-hoon

 

Related Tags

Shop Teach You a Lesson

Go to Netflix Shop

Discover More Who’s Who

  • Office Romance Cast: Fly High with Jennifer Lopez, Brett Goldstein, and More
    A guide to the ensemble of this sharp, funny workplace rom-com.
  • Here’s how to keep track of everyone in the South Carolina small town.
  • Here’s how to keep track of everyone in the small town of Serenity, South Carolina.
  • Everything you need to know about the friend group and their A-list connections.
  • Alfred Molina and Geena Davis as retirees in a new sci-fi series.
  • Matthew Law and Y’lan Noel lead the thrilling series from the creator of Power.
  • A deep dive on the romantic drama’s characters and the actors who play them.

Discover More Action

  • If you think animation is just for kids, think again.
  • Plus The Polygamist, Drinking Buddies, Song Sung Blue, and more.
  • King and Queen of the Ring semifinals matches are going down.
  • Yip, yip, let’s get some answers from the showrunner.
  • Perfect for road trips, sleepovers, and sunburn recovery mode.
  • Overwhelmed with grief, the hardened assassin loses control.
  • Kim Moo-yul and Lee Sung-min make the principal's office look like paradise.
  • When money’s on the line, these contestants’ true colors shine.

Latest News

  • Maternal Instinct Tells the True Story of a Terrifying Pregnancy Secret
    Smiling couple sitting on a blanket outdoors in a grassy field, with trees in the background, wearing casual clothes and cowboy hat, enjoying a relaxed moment in nature during daylight.

Popular Now

  • In FIFA World Cup: Launch Edition game, your living room becomes a stadium.
  • Stream Voicemails for Isabelle, Office Romance, a new season of Avatar: The Last Airbender, and more.
  • The Bridgerton onscreen brothers discuss their offscreen bond.