‘Undercover High School’ K-drama is a 2025 South Korean action-comedy drama about Jung Hae-Seong, a National Intelligence Service (NIS) agent demoted after a failed mission. Assigned to recover lost gold bars, he infiltrates Byeongmoon High School disguised as a student. Balancing his covert operation with the chaos of school life, he encounters Oh Soo-A, a devoted history teacher who finds him oddly familiar. As secrets unravel, Hae-Seong must navigate friendships, enemies, and his growing connection with Soo-A. Blending espionage, humor, and heartfelt moments, the drama delivers an exciting mix of mystery and school-life storytelling.
Jung Hae Seong (Seo Kang Joon)
Jung Hae-Seong is a highly skilled but reckless detective who is forced to disguise himself as a high school student. While trying to maintain his cover, he unexpectedly gets drawn into real high school problems like friendships, rivalries, and even first love. Jung Hae-Seong’s struggles with teenage life reveal an unexpectedly humorous and adaptable side as he balances duty, deception, and unexpected connections.
Oh Soo A (Jin Ki Joo)
Oh Soo A is a passionate and dedicated Korean history teacher at Byeongmoon High School. Known for her strong principles and deep care for her students, she strives to make learning meaningful while protecting them from the harsh realities of the world. When Jung Hae-Seong arrives, she senses something unusual about him, especially his resemblance to someone from her past. As she gets entangled in his secret mission, Soo-A’s warmth, intelligence, and determination shine through, revealing her struggles with trust, past regrets, and the unexpected chaos that Hae Seong brings into her life.
Seo Myeong Ju (Kim Shin Rok)
Seo Myeong-Ju is the sharp and ambitious vice principal of Byeongmoon High School. Known for her meticulous nature and no-nonsense attitude, she keeps a close eye on both students and staff, ensuring the school runs efficiently. Unlike Principal Choi Sung-Tae, she is less tolerant of disruptions and quickly grows suspicious of Jung Hae-Seong’s true identity. Behind her strict demeanor, Myeong-Ju is deeply invested in the school’s prestige and has her own ambitions to rise in the education field. As tensions build, her sharp instincts and determination make her a formidable obstacle in Hae-Seong’s undercover mission.
Lee Ye Na (Kim Min Ju)
Lee Ye Na is the confident and ambitious student council president of Byeongmoon High School. As the daughter of Vice Principal Seo Myeong-Ju, she carries the weight of high expectations and strives for perfection in everything she does. Known for her intelligence and strong leadership, she upholds school rules with firm authority, often clashing with those who challenge them. However, beneath her composed and disciplined demeanor lies a young woman struggling to balance her mother’s strict demands with her desires. As Jung Hae-Seong’s presence stirs chaos, Ye-Na finds herself questioning the truth and where her loyalties truly lie.
Park Tae Soo (Jang Seong Beom)
Park Tae-Soo is the charismatic and fearless leader of Byeongmoon High School’s most notorious gang, as well as a student council member with deep political ties. As the son of a three-term National Assembly member from Yeouido, he carries both privilege and pressure, though he prefers the streets over politics. Known for his strength and sharp instincts, he commands respect but often clashes with authority. Initially seeing Jung Hae-Seong as a threat, he later becomes an unlikely ally. Beneath his tough exterior lies a strong sense of loyalty, forcing him to choose between his reputation and doing what’s right.
My Thoughts
Based on this ‘Undercover High School’ K-drama synopsis, the series presents a fun yet action-packed take on high school life with a thrilling investigative twist. The drama explores the humorous struggles of an adult trying to fit into a teenage environment while balancing suspenseful moments involving crime-solving. With engaging action sequences, comedic interactions, and heartfelt relationships, ‘Undercover High School’ offers a fresh and entertaining narrative that blends mystery, humor, and heartwarming moments seamlessly.