Undercover High School is Seo Kang Joons latest project after his military service. The film aired on the evening of February 21 and quickly attracted the attention of the audience. In the first episode, the drama achieved a viewership rating of 5.6% and increased to 6.6% for episodes 2 and 3. Episode 4 of the drama achieved a rating of 8.3%.
Donga (Korea) reviews that, in addition to the content, the scoring factor of Undercover High School comes from Seo Kang Joons attractive acting. After a series of familiar roles in romantic films, the actor has shown a completely new side of the character Jeong Hae Seong.
The character of the star born in 1993 is an elite agent of the National Intelligence Service (NIS). He worked secretly as a student at Byungmun High School to search for the lost gold of Emperor Gojong.
On screen, Seo Kang Joon attracted with his handsome appearance. Korean newspapers praised the male star despite being over 30 years old, he still maintained his youthful appearance when wearing high school uniforms.

Along with that, the character "trump card NIS" makes the film more attractive thanks to beautiful action scenes with a high-speed car chase to battles with the thugs.
Jeong Hae Seong's efforts to understand teenage words, or perform dances to participate in student groups... are also factors that create humor and score points with viewers.
According to the media, Undercover High School is the best project in Seo Kang Joons career, while the audience praised the actor for being completely transformed.
Previously at the press conference, Seo Kang Joon confessed that he was attracted to the way the film combined the smooth elements of romance, thriller, comedy and action.
The actor revealed that he spent a lot of time reflecting on the characters, as well as being trained in an action school to be able to portray difficult scenes most realistically. Thanks to this effort, his reputation increased.
Most recently, Good Data Corporation announced Seo Kang Joon topped the ranking of most favorite actors of the week. This is also the first time he has achieved this achievement in his career.
Meanwhile, Undercover High School is the top drama on the Korean TV and OTT (online) charts this week.