Undercover High School

Undercover High School is a 2025 South Korean action comedy spy television series written by, directed by Choi Jung-in, and starring Seo Kang-joon, Jin Ki-joo, and Kim Shin-rok. The series depicts a man who is an NIS agent goes undercover as a high school student. It aired on MBC TV from February 21, to March 29, 2025, every Friday and Saturday at 21:50. It is also available for streaming on TVING and Wavve in South Korea, and on Viu, Kocowa and Viki in selected regions.

WWW program.imbc.com/Undercov...

Synopsis

Jeong Hae-seong, a demoted NIS agent following a major incident that occurred during an operation, is tasked with a special mission of tracking down the whereabouts of Emperor Gojong's missing gold bars. Hae-seong hides his identity, goes undercover as a high school student at Byeongmun High School, and meets Oh Su-a, his homeroom teacher. Su-a, a devoted teacher to her students, begins to notice the similarities between Hae-seong and her childhood first love, who left her heartbroken and filled with painful memories.

Cast and characters

Main

Seo Kang-joon as Jeong Hae-seong / Jeong Si-hyun
* Yu Ji-wan as young Jeong Si-hyun
Jin Ki-joo as Oh Su-a / Oh Bong-ja
* Park Seol-ha as young Oh Bong-ja
Kim Shin-rok as Seo Myeong-ju

Supporting

NIS people

Jeon Bae-soo as An Seok-ho
Jo Bok-rae as Go Yeong-hun
as Park Mi-jeong
Lee Seo-hwan as Kim Hyung-bae
as Gong Jin-sang

Student Council of Byeongmun High School

Kim Min-ju as Lee Ye-na
Park Se-hyun as An Yu-jeong
as Park Tae-soo
Lee Hyun-so as Han Seung-jae
Yoon Chae-bin as Yoon Chae-rin
Kim Sun-min as Ji Hyun-joon

Students of Byeongmun High School

as Lee Dong-min
Jeong Soo-hyun as Im Yoon-cheol
Kang Pil-jun as Son Beom-sik
as Choi Su-jin
Kim Seung-beom as Kim Ho-jin

Teacher's office of Byeongmun High School

as Park Jae-mun

The principal of Byeongmun High School who is Myeong-ju's loyal henchman.

as Baek Kwang-du,
Lee Min-ji as Kim Ri-an
Noh Jong-hyun as Lee Jun-ho

Others

as Im Cheong-ha
Kim Soo-jin as Jang Man-ok
Gu Min-hyuk as Kim Hyeon-ho
Kim Eui-sung as Seo Byeong-mun
Oh Eui-shik as Jeong Jae-Hyeon

Production

Development

The series began its production and is planned by Namkoong Seong-woo, written by, directed by Choi Jung-in, and produced by Neo Entertainment and Slingshot Studios. In addition, it aimed to air in early 2025.

Casting

In March 2024, Seo Kang-joon was reportedly in talks as the lead actor and his agency told the media that he was positively reviewing it. This was Seo's first work after completing his military service in May last year as well as comeback to the small screen after 2022 TV series Grid. In May 2024, Jin Ki-joo and Kim Min-ju were reportedly cast to work along Seo with the former as the female lead in the series. In June 2024, MBC confirmed that Seo and Jin would appear as the lead actors for the series. This was also Seo's first MBC drama comeback after appearing in Splendid Politics. The same month, Kim Shin-rok was reportedly confirmed to cast July 2024.

Filming

Principal photography began in the first half of 2024.

Release

MBC announced that Undercover High School would be broadcast in a Friday–Saturday timeslot in February 2025. The series was confirmed to premiere on MBC TV on February 21, at 21:50. It is also available for streaming on TVING and Wavve in South Korea, and on Viu, Kocowa and Viki in selected regions.