
Seo Kang Joon is regaining popularity with his highly anticipated comeback, three years after completing his military service. His return to the small screen has been met with both strong viewership ratings and widespread buzz, solidifying his rising popularity.
MBC’s 'Undercover High School,' starring Seo Kang Joon, premiered on February 21 and has been rapidly gaining traction with audiences. The drama started with a 5.6% viewership rating (Nielsen Korea) and has since climbed steadily, reaching 6.6% by episodes 2 and 3, and an impressive 8.3% by episode 4.

A major factor behind the drama’s success is Seo Kang Joon’s captivating performance, which fans have described as a "one-man show." Known primarily for his romance roles, he has taken this opportunity to showcase a completely different side of himself, proving he has been honing his acting skills.
In 'Undercover High School,' Seo Kang Joon plays Jung Hae Sung, an elite National Intelligence Service (NIS) agent who goes undercover as a high school student to track down the lost gold of Emperor Gojong. Despite being in his 30s, he seamlessly fits into a school uniform and effortlessly balances intense action scenes with comedic moments.

His portrayal of a "NIS ace" shines in high-octane sequences, from high-speed car chases to intense one-against-many fights with gangsters. His agile movements and impressive stunt work have heightened the drama’s immersion, earning praise from viewers who describe the show as "thrilling and refreshing." Fans have hailed his performance as a career-defining role, with comments such as "Seo Kang Joon has fully awakened in this drama" and "This is his best character yet."
Adding to the entertainment, Seo Kang Joon’s comedic timing brings an extra layer of charm. His character hilariously struggles to understand teenage slang and even performs a dance routine to join the student council, making for some of the show’s funniest moments.

During the press conference, Seo Kang Joon expressed his excitement about the project, saying, "I was drawn to the way this drama seamlessly blends romance, thriller, comedy, and action." His versatility is paying off, as Undercover High School has dominated both TV and OTT platform buzz rankings for two consecutive weeks.
According to the latest Good Data Corporation report, 'Undercover High School' ranked No. 1 in both TV and OTT categories, while Seo Kang Joon himself topped the actor rankings for the first time in his career.