From Mask Girl to D.P.: Exploring Lee Jun-young’s dark evolution as his Weak Hero Class 2 villain role earns him “Joker of Korea” status

Lee Jun-young started out as "Jun" of the K-pop idol group U-KISS back in 2014, and has gradually established himself as a credible actor across television and film. He took his first acting role in the tvN drama Avengers Social Club (2017), which paved the way for his growth as a screen actor from an idol singer.

Since his screen debut, the actor has transitioned from supporting and romantic roles to darker, more complex characters.

He has also demonstrated his skills in musical theatre, most notably Swag Age: Shout Out, Chosun! – and received the Male Rookie (Best New Actor) award for that performance at the 5th Korea Musical Awards. His recent portrayal of Geum Seong-jae in Weak Hero Class 2 (2025) has been widely praised, marking a significant milestone in his acting evolution.

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Lee Jun-young’s steady rise: From romantic leads to a critically acclaimed villain role in the Weak Hero Class 2

Over the years, he has transitioned from romantic hero roles and lighthearted dramas to dark, psychological roles in serious genres. Through performances across network dramas, streaming platforms like Netflix originals, and Amazon Prime releases, Lee has not only broadened his range but also challenged audience expectations.

His role as Geum Seong-jae in Weak Hero Class 2 (2025) stands as a career-defining moment, bringing renewed attention to his versatility and acting depth. The following is an overview of his career progression—from early breakthroughs and romantic leads to Netflix titles and acclaimed villain roles.

Breakthrough in dramas, lead roles, and romances

Lee Jun-young in When Life Gives You Tangerines (Image via Netflix)

Lee's initial big on-screen breakthrough was with the MBC family drama Goodbye to Goodbye (2018). His performance in the drama earned him the Best New Actor award at both the 2018 MBC Drama Awards and the 2018 Korea Cultural Entertainment Awards.

In OCN's thriller Class of Lies (2019), he portrayed Yoo Beom-jin, a top student and son of a politician. He also made appearances in the SBS drama Backstreet Rookie in 2020.

In 2020, Lee Jun-young landed his first lead role in the quirky romantic comedy Please Don't Date Him. He went on to star in romantic-but-offbeat dramas such as Imitation and Let Me Be Your Knight in 2021, frequently playing idolised pop stars or musicians – roles that were well-suited to his background as a singer-turned-actor.

The most significant jump was, however, when Netflix paired him with Girls' Generation's Seohyun in Love and Leashes (2022). In this movie, Lee Jun-young played Jung Ji-hoo, a seemingly mild-mannered office worker with a secret BDSM fetish. His earthy, understated acting gained worldwide acclaim.

In 2022, he took on dual roles in May I Help You? as Butler Kim/Kim Tae-hee. His nuanced portrayal earned him the Best Actor Award at the 2022 Asia Artist Awards and a nomination for Excellence Award, Actor in a Miniseries at the 2022 MBC Drama Awards.

Then again in 2023 the actor appeared in Dreaming of a Freaking Fairy Tale as Moon Cha-min, which explored romantic comedy in a modern fairytale setting. He also took on leading roles in Melo Movie (Hong Si-jun) and When Life Gives You Tangerines (Park Yeong-beom), which premiered in 2024 and 2025. In early 2025, he also made a cameo appearance as King Sejong in episode 12 of The Queen Who Crowns.

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Expansion into darker characters: Action and crime

Lee Jun-young in The Queen Who Crowns (Image via Viki)

Lee Jun-young’s image began to shift with his cameo in Netflix’s D.P. (2021), where he played Jung Hyun-min in episode 3. Though brief, the role hinted at a more serious acting direction. He also had a supporting role in the satirical horror thriller Mask Girl (2023).

That same year, Lee took on the role of Han Soo-gang in Brave Citizen (2023), an Amazon Prime action thriller co-starring Shin Hye-sun. In Brave Citizen Lee delivered one of his most rugged performances to date, playing a violent student antagonist.

The performance was well-received for demonstrating Lee Jun-young's capacity to take on a darker, brooding character – a far cry from his previous "nice guy" protagonists. This performance also earned him the Best Acting Performance Award at the 2023 Asia Artist Awards.

That same year, he also made a cameo as Choi Bu-yong in episode 4 of Netflix’s Mask Girl, a psychological thriller series. His work in both Brave Citizen and Mask Girl was recognised with the Scene Stealer of the Year award at the 2023 Scene Stealer Festival. Additionally, he was nominated for Best New Actor in a Series at the 2024 Director's Cut Awards for Mask Girl.

In early 2024, Lee appeared in the Netflix film Badland Hunters as Choi Ji-wan, an action role that continued his trajectory into grittier narratives. He also starred in The Impossible Heir as Kang In-ha, a character caught in a corporate inheritance battle.

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Weak Hero Class 2 (2025): an acclaimed villain role

Lee Jun-young in Weak Hero Class 2 (Image via Netflix)

In 2025, with the Netflix hit Weak Hero Class 2, Lee Jun-young stars as Geum Seong-jae, the cold-blooded lieutenant of a school gang named 'Union' led by Na Baek-jin (Bae Na-ra). In this role, Lee completely discards his idol persona, playing a vicious school thug with an icily captivating performance.

Lee Jun-young received critical acclaim for his performance in Weak Hero Class 2 as Geum Seong-jae, a school gang's second-in-command. The character's violent and unpredictable nature contrasted sharply with Lee’s earlier roles and showcased his growth as an actor.

Weak Hero Class 2, instantly after release, became an international phenomenon, peaking at #2 on Netflix's global chart just after airing, and reviews credited Lee's work as exemplary. Critics praised his performance, with some referring to him as the "Joker of Korea" for his unsettling portrayal.

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All eight episodes of Weak Hero Class 2 are available to stream on Netflix.