Undercover High School

Undercover High School (Korean: 언더커버 하이스쿨) is a South Korean action-comedy television series that premiered in 2025. The drama was broadcast on the MBC network.

Plot

The series follows Jung Hae-Seong (played by Seo Kang-Joon), an elite field agent for the National Intelligence Service (NIS). Following a significant incident during a mission, he is demoted and assigned to a new operation: locating the missing gold bars of King Gojong. To complete this mission, Hae-Seong must go undercover as a student at the prestigious Byeongmoon High School. While there, he encounters his homeroom teacher, Oh Soo-A (Jin Ki-Joo), a contract teacher of Korean history who is deeply dedicated to her students. Their meeting is complicated by the fact that Hae-Seong resembles a figure from Soo-A's past who caused her significant emotional distress.

Production

The series was directed by Choi Jung-In and written by Im Young-Bin. It aired on Fridays and Saturdays at 21:50 on MBC. The project is notable as the first acting role for lead actor Seo Kang-Joon following his completion of mandatory military service on May 22, 2023.

Seo Kang-Joon portrays the lead character, Jung Hae-Seong.

Jin Ki-Joo stars as the teacher Oh Soo-A.

Cast

Seo Kang-Joon as Jung Hae-Seong
Jin Ki-Joo as Oh Soo-A
Kim Shin-Rok as Seo Myeong-Joo