Undercover High School
| Company type | Television series |
|---|---|
| Industry | Entertainment |
| Founded | 2025 |
| Headquarters | South Korea |
| Products | Television drama |
| Parent | MBC TV |
Undercover High School () is a 2025 South Korean action comedy spy drama scripted by , with direction by Choi Jung-in. The series features performances by Seo Kang-joon, Jin Ki-joo, and Kim Shin-rok. The storyline centers on a National Intelligence Service (NIS) operative who, after being demoted, infiltrates a high school under an assumed identity. Broadcast on MBC TV from February 21 to March 29, 2025, it aired Fridays and Saturdays at 21:50 KST. Additionally, the show is accessible for streaming through TVING and Wavve within South Korea, and via Viu, Kocowa, and Viki in selected international markets.
Synopsis
Following a failed mission, Jeong Hae-seong, an NIS agent stripped of his rank, receives a covert assignment to recover the lost gold bars of Emperor Gojong. To carry out this mission, he assumes the role of a student at Byeongmun High School. There, he crosses paths with Oh Su-a, his homeroom teacher, who is deeply committed to her pupils. Su-a notices qualities in Hae-seong that remind her of her first love from childhood, evoking bittersweet emotions.
Main
- Seo Kang-joon portrays Jeong Hae-seong / Jeong Si-hyun
- Yu Ji-wan appears as young Jeong Si-hyun
- A top agent in the Domestic Team 4 of the NIS, assigned to find Emperor Gojong’s missing gold.
- Jin Ki-joo plays Oh Su-a / Oh Bong-ja
- Park Seol-ha depicts young Oh Bong-ja
- The homeroom teacher and temporary Korean history instructor at Byeongmun High School who interacts closely with Hae-seong.
- Kim Shin-rok as Seo Myeong-ju
- Chairperson of both the Byeongmun Foundation and Byeongmun High School; mother to Ye-na.
NIS personnel
- Jeon Bae-soo as An Seok-ho
- Leader of Domestic Team 4 at the NIS; serves as both mentor and paternal figure to Hae-seong.
- Jo Bok-rae as Go Yeong-hun
- Junior operative working under Hae-seong within the NIS.
- as Park Mi-jeong
- Another junior agent assisting Hae-seong.
- Lee Seo-hwan as Kim Hyung-bae
- Oversees the domestic division at the NIS.
- as Gong Jin-sang
- Chief of NIS Domestic Team 1 and former classmate of An Seok-ho.
Student Council of Byeongmun High School
- Kim Min-ju as Lee Ye-na: President of the student council and daughter of Myeong-ju.
- Park Se-hyun as An Yu-jeong: Member of the student council; daughter of Seok-ho and younger sibling to Hae-seong.
- as Park Tae-soo: Student council member with a father serving three terms in the National Assembly from Yeouido.
- Lee Hyun-so portrays Han Seung-jae: Student council member; son of the CEO of Han Young Law Firm, one of South Korea’s prominent legal firms.
- Yoon Chae-bin as Yoon Chae-rin: Student council member and aspiring idol trainee.
- Kim Sun-min plays Ji Hyun-joon: Vice-president of the student council.
Students of Byeongmun High School
- as Lee Dong-min: A student targeted by bullying from Tae-soo’s clique.
- Jeong Soo-hyun as Im Yoon-cheol: Known for verbal bullying within the class.
- Kang Pil-jun portrays Son Beom-sik: Class bully recognized for his keen observational skills.
- as Choi Su-jin: A student highly knowledgeable about social media trends.
- Kim Seung-beom as Kim Ho-jin: Provides information related to internet broadcasting and content creation.
Byeongmun High School Faculty Room
- portraying Park Jae-mun
The principal of Byeongmun High School and a devoted supporter of Myeong-ju.
- portraying Baek Kwang-du
The vice-principal serving at Byeongmun High School.
- Lee Min-ji portraying Kim Ri-an
A physical education teacher and close confidante of Su-a.
- Noh Jong-hyun portraying Lee Jun-ho
A mathematics instructor at the school who harbors feelings for Su-a.
Additional Characters
- portraying Im Cheong-ha
Su-a’s mother and proprietor of the restaurant Have a Drink With Su-a, operating for over a decade.
- Kim Soo-jin portraying Jang Man-ok
Wife to Seok-hi, mother to Yoo-jung, and a maternal presence in Hae-seong’s life.
- Gu Min-hyuk portraying Kim Hyeon-ho
The security personnel assigned to Byeongmun High School.
- Kim Eui-sung portraying Seo Byeong-mun
A traitor to the nation and guardian of Emperor Gojong’s secret safe.
- Oh Eui-shik portraying Jeong Jae-Hyeon
Father of Hae-seong and an NIS agent who has been missing for 22 years.
Development
The project was spearheaded by Namkoong Seong-woo, with the script authored by , direction by Choi Jung-in, and production handled by Neo Entertainment alongside Slingshot Studios. The series was planned for release in early 2025.
Casting
In March 2024, Seo Kang-joon entered negotiations to headline the series, marking his first role following military discharge in May 2023 and his return to television since the 2022 drama Grid. By May 2024, Jin Ki-joo and Kim Min-ju were confirmed to join Seo, with Jin taking on the female lead role. In June 2024, MBC officially announced Seo and Jin as leads, representing Seo's first MBC drama since Splendid Politics (2015). That same month, Kim Shin-rok was cast in a significant role as chairman.
Filming
Principal photography began in early 2024.
Release
Undercover High School is set to air on Munhwa Broadcasting Corporation (MBC) during the Friday–Saturday prime time slot commencing February 21, 2025, at 21:50 KST. The show will be broadcast on MBC TV and available for streaming via TVING and Wavve within South Korea, as well as through Viu, Kocowa, and Viki across selected international territories.
Viewership
| Ep. | Original Air Date | Average Audience Share (Nielsen Korea) | |
|---|---|---|---|
| Nationwide | Seoul | ||
| 1 | February 21, 2025 | 5.6% (12th) | 5.8% (9th) |
| 2 | February 22, 2025 | 6.6% (5th) | 6.5% (4th) |
| 3 | February 28, 2025 | 6.6% (9th) | 6.7% (6th) |
| 4 | March 1, 2025 | 8.3% (3rd) | 8.3% (3rd) |
| 5 | March 7, 2025 | 7.2% (6th) | 7.0% (6th) |
| 6 | March 8, 2025 | 6.7% (3rd) | 7.1% (3rd) |
| 7 | March 14, 2025 | 6.8% (6th) | 6.3% (8th) |
| 8 | March 15, 2025 | 6.1% (4th) | 6.1% (3rd) |
| 9 | March 21, 2025 | 6.1% (7th) | 5.8% (8th) |
| 10 | March 22, 2025 | 5.4% (5th) | 5.3% (5th) |
| 11 | March 28, 2025 | 6.0% (6th) | 6.3% (7th) |
| 12 | March 29, 2025 | 5.8% (4th) | 5.8% (4th) |
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External links
- 2025 South Korean TV series premieres
- 2025 South Korean TV series finales
- Korean-language television programs
- Korean-language Viu exclusive international streaming content
- MBC TV drama series
- South Korean action dramas
- South Korean comedy dramas
- South Korean espionage dramas
- Television shows set in 2003
- Television shows set in 2025
- Korean-language Viu (streaming media) exclusive international distribution programming