Seo Kang-joon has become one of South Korea’s most beloved actors, captivating audiences with his versatile performances and undeniable charm. As we look back on his career up to 2025, let’s explore the top 10 Korean dramas and movies that showcase his incredible talent and range as an actor.
1. Undercover High School (2025)
Seo Kang-joon’s latest drama, “Undercover High School,” marks his triumphant return to television after a three-year hiatus. In this exciting series, he plays Jung Hae-sung, a skilled National Intelligence Service (NIS) agent who goes undercover as a high school student. His mission? To find Emperor Gojong’s lost gold treasure.
The drama perfectly blends action, comedy, and heart-warming moments. Seo Kang-joon’s portrayal of Hae-sung shows off both his action skills and his comedic timing. Viewers get to enjoy watching him navigate the chaos of high school life while trying to maintain his cover as a top-secret agent.
What makes this drama special is how it lets Seo Kang-joon show a lighter, more playful side of his acting. It’s a refreshing change from some of his more serious roles in the past.
2. When the Weather Is Fine (2020)
This romantic drama tells the story of Mok Hae-won (played by Park Min-young), a cellist who returns to her small hometown after facing difficulties in Seoul. There, she reconnects with Im Eun-seob (Seo Kang-joon), her former classmate who now runs a bookstore.
Seo Kang-joon’s portrayal of Eun-seob is gentle and warm, perfectly capturing the character’s quiet strength and deep emotions. The slow-burning romance between Eun-seob and Hae-won is beautifully depicted, with Seo Kang-joon’s nuanced performance bringing depth to every scene.
Set against the backdrop of a snowy small town, this drama offers a cozy, healing atmosphere. Seo Kang-joon’s chemistry with Park Min-young is palpable, making their love story feel genuine and touching.
3. Watcher (2019)
In this gripping thriller, Seo Kang-joon plays Kim Young-goon, a police officer who joins an internal affairs investigation team. The drama follows three characters whose lives were changed by a tragic event 15 years ago, as they work together to uncover the truth.
Seo Kang-joon’s performance as Young-goon is intense and compelling. He perfectly captures the character’s complex emotions, balancing Young-goon’s cold exterior with hints of his hidden warmth and determination.
This role allowed Seo Kang-joon to showcase his ability to handle more mature, serious characters. His on-screen presence is powerful, holding his own alongside veteran actors like Han Suk-kyu and Kim Hyun-joo.
4. Are You Human? (2018)
This science fiction romance drama sees Seo Kang-joon taking on dual roles as Nam Shin, a wealthy company heir, and Nam Shin III, an advanced AI robot created in Nam Shin’s image. When Nam Shin falls into a coma, Nam Shin III takes his place to protect the family company.
Seo Kang-joon’s ability to portray two distinct characters is truly impressive. He seamlessly switches between the cold, arrogant Nam Shin and the curious, kind-hearted Nam Shin III. His performance brings depth to both characters, making viewers empathize with the robot’s journey to understand human emotions.
The drama explores themes of humanity, love, and what it means to be “real.” Seo Kang-joon’s nuanced acting brings these complex ideas to life, making “Are You Human?” a thought-provoking and emotionally engaging watch.
5. The Third Charm (2018)
This romantic comedy-drama follows the 12-year relationship between On Joon-young (Seo Kang-joon) and Lee Young-jae (Esom). The story is told in three parts, showing how their relationship evolves as they grow from their 20s into their 30s.
Seo Kang-joon’s portrayal of Joon-young is both charming and realistic. He perfectly captures the character’s growth from a nerdy, overly cautious 20-year-old to a more confident and mature adult. His chemistry with Esom feels natural and sincere, making their love story both sweet and relatable.
What sets this drama apart is its realistic depiction of long-term relationships, showing both the ups and downs. Seo Kang-joon’s performance adds depth to this portrayal, bringing out the complexities of love and personal growth.
6. Entourage (2016)
Based on the popular American series of the same name, “Entourage” follows the life of rising actor Cha Young-bin (Seo Kang-joon) and his group of friends as they navigate the glamorous and cutthroat world of the Korean entertainment industry.
This role allowed Seo Kang-joon to show a different side of his acting skills. As Young-bin, he portrays a charismatic and sometimes naive young star, capturing both the excitement and pressures of sudden fame. His performance is natural and engaging, making Young-bin’s journey through the ups and downs of celebrity life feel authentic.
While the drama received mixed reviews, Seo Kang-joon’s performance was widely praised. He brought charm and depth to Young-bin, making him a relatable and likable protagonist despite the character’s flaws.
7. Cheese in the Trap (2016)
Based on a popular webtoon, this college romance drama stars Seo Kang-joon as Baek In-ho, a talented pianist with a troubled past. While he’s not the main lead, Seo Kang-joon’s portrayal of In-ho stole many viewers’ hearts and showcased his ability to bring complex characters to life.
In-ho is a character with many layers – he’s brash and confrontational on the surface, but hides deep pain and vulnerability. Seo Kang-joon perfectly captures this duality, making In-ho both frustrating and endearing. His chemistry with Kim Go-eun, who plays the female lead Hong Seol, is particularly noteworthy.
This role was a turning point in Seo Kang-joon’s career, earning him widespread recognition and praise for his acting skills. Many viewers found themselves rooting for In-ho, testament to Seo Kang-joon’s ability to bring depth and charm to his characters.
8. A Year-End Medley (2021)
This heartwarming romantic comedy film features an ensemble cast, with Seo Kang-joon playing Lee Kang, a hotel guest with a unique story. The movie weaves together multiple love stories all taking place in a hotel during the New Year holiday season.
Although Seo Kang-joon’s role is not as large as in some of his other projects, he makes a strong impression in his limited screen time. His portrayal of Lee Kang is sweet and sincere, adding to the film’s overall warm and festive atmosphere.
This movie showcases Seo Kang-joon’s ability to shine even in a large ensemble cast. His scenes are memorable and touching, contributing to the film’s exploration of different types of love and human connections.
9. Grid (2022)
In this sci-fi mystery thriller, Seo Kang-joon plays Kim Sae-ha, a Bureau employee searching for the truth about a mysterious entity known as “the Ghost” that once saved humanity. The drama blends elements of science fiction, mystery, and action, creating a unique and gripping story.
Seo Kang-joon’s performance as Sae-ha is intense and compelling. He perfectly captures the character’s determination and growing confusion as he uncovers more about the Ghost and the secrets surrounding it. His ability to convey complex emotions adds depth to the intricate plot.
This role allowed Seo Kang-joon to further demonstrate his versatility as an actor. The sci-fi setting and complex narrative gave him the opportunity to tackle a character unlike any he had played before, and he rose to the challenge admirably.
10. The Beauty Inside (2015)
While Seo Kang-joon only has a small role in this romantic fantasy film, it’s worth mentioning as it was one of his early film appearances. The movie tells the story of a man who wakes up in a different body every day, and the woman who loves him despite this unusual condition.
Seo Kang-joon appears as one of the many forms of the main character. Even in his brief appearance, he manages to capture the essence of the character, contributing to the film’s exploration of love that goes beyond physical appearance.
This early role hinted at Seo Kang-joon’s potential as an actor, which he has certainly fulfilled in the years since.
