Lee Jun-young first captured the spotlight as “Jun,”a member of the K-pop idol group U-KISS, in 2014. Since then, he has evolved into a notable actor, earning acclaim in both television and film. His acting debut in the tvN series Avengers Social Club (2017) marked the beginning of his successful transition from idol singer to serious performer.
Following his debut, Lee has skillfully navigated the acting landscape, shifting from supporting roles and light romantic characters to more intricate and challenging roles.
He showcased his talents in musical theater with notable performances, including in Swag Age: Shout Out, Chosun! for which he received the Male Rookie (Best New Actor) award at the 5th Korea Musical Awards. His recent portrayal of Geum Seong-jae in Weak Hero Class 2 (2025) has garnered widespread praise, underscoring a pivotal moment in his acting journey.
From Romantic Leads to a Notorious Villain: The Evolution of Lee Jun-young
Over the years, Lee has successfully transitioned from the charming romantic leads typical in lighter dramas to the psychological depths of more serious storytelling. His performances span network television and popular streaming platforms, including Netflix and Amazon Prime, further expanding his versatility and defying audience expectations.
His character Geum Seong-jae in Weak Hero Class 2 has emerged as a cornerstone of his career, showcasing his range and depth as an actor. Below is a detailed analysis of Lee’s career trajectory, highlighting his journey from early roles in romantic dramas to critically acclaimed performances in intense, darker narratives.
Early Breakthroughs: Romantic Leads and Dramatic Roles
Lee’s significant breakthrough came with the MBC family drama Goodbye to Goodbye (2018), which earned him the Best New Actor award at both the MBC Drama Awards and the Korea Cultural Entertainment Awards.
In 2019, he showcased his talent in OCN’s thriller Class of Lies, portraying Yoo Beom-jin, a gifted student with a politically connected background. The subsequent year, he made a splash in the SBS drama Backstreet Rookie.
2020 marked a turning point as Lee starred in his first lead role in the whimsical romantic comedy Please Don’t Date Him. He subsequently appeared in offbeat romantic dramas like Imitation and Let Me Be Your Knight in 2021, often playing the role of an idol or musician—roles that resonated with his established persona as a singer-turned-actor.
A landmark moment was his collaboration with Girls’ Generation’s Seohyun in the Netflix film Love and Leashes (2022), where he portrayed Jung Ji-hoo, an office worker with a hidden BDSM interest. His grounded performance received international acclaim.
The same year, Lee took on a dual role in May I Help You?, portraying both Butler Kim and Kim Tae-hee, for which he received the Best Actor Award at the 2022 Asia Artist Awards and a nomination for Excellence Award in a Miniseries at the MBC Drama Awards.
In 2023, he further showcased his versatility in Dreaming of a Freaking Fairy Tale as Moon Cha-min and played leading roles in Melo Movie and When Life Gives You Tangerines, premiering in 2024 and 2025, respectively. He also made a cameo as King Sejong in The Queen Who Crowns.
Delving into Darker Characters: Action and Crime Roles
Lee’s shift in image began with his cameo in Netflix’s D.P. (2021), where he hinted at a more serious acting path. His supporting role in the satirical horror-thriller Mask Girl (2023) reinforced this transition.
In 2023, he took on the role of Han Soo-gang in the Amazon Prime action thriller Brave Citizen, where he demonstrated his ability to portray a gritty antagonist, showcasing a rugged side of his acting. This role marked a significant departure from his previous “nice guy”portrayals and earned him the Best Acting Performance Award at the Asia Artist Awards.
Lee further displayed his evolving skills with a cameo in Mask Girl and was recognized with the Scene Stealer of the Year award for his performances in both this series and Brave Citizen. 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 took on an action role in the Netflix film Badland Hunters as Choi Ji-wan, further solidifying his place in narratives that explore darker themes. He also starred in The Impossible Heir as Kang In-ha, a character embroiled in a corporate inheritance struggle.
Geum Seong-jae in Weak Hero Class 2 (2025): The Rise of a Villain
In 2025, Lee Jun-young captivated audiences in the Netflix sensation Weak Hero Class 2, where he starred as Geum Seong-jae, the cold-blooded second-in-command of a school gang known as ‘Union,’ led by Na Baek-jin (Bae Na-ra). This role marked a stark departure from his previous image, allowing him to delve into a character marked by violence and complexity.
Critics widely praised Lee’s performance in Weak Hero Class 2, recognizing it as a critical high point in his career. His unsettling portrayal earned him accolades, with some reviewers dubbing him the “Joker of Korea,”reflecting his ability to embody a menacing presence.
The series quickly became a global phenomenon, peaking at #2 on Netflix’s worldwide rankings shortly after its release. Lee Jun-young’s portrayal stood out, with critics calling it exemplary. All eight episodes of Weak Hero Class 2 are currently available for streaming on Netflix.