The 'Weak Hero Class 2' Cast: Your Guide

(L to R) Lee Min-jae as Go Hyuntak, Ryeo Un as Park Humin, Choi Min-yeong as Seo Juntae, Park Ji-hoon as Yeon Sieun in Weak Hero Class 2 — (Image credit: Darae Lee/Netflix)

Netflix's thriller K-drama Weak Hero Class 2 is back for a new semester. For anyone who missed the action series's debut on the streamer last month, Weak Hero Class 1 first premiered in 2022, introducing viewers to top student and cutthroat fighter Yeon Si-eun (Park Ji-hoon). Throughout the first season, the calculating yet kind-hearted teen was pulled into school bullying and gang violence, and the installment ended with Si-eun expelled from his old school. Weak Hero Class 2 continues Si-eun's story, as he enrolls in Eunjang High and faces off against an even bigger threat, as the trauma of his past still lingers.

As fans of the original webtoon Weak Hero know, Weak Hero Class 2 introduces a new cast of lovable friends and intriguing antagonists for Si-eun to meet. The Netflix K-drama has recruited several of the world of Korean entertainment's most talented rising stars, including alums of the streaming giant's most popular Korean shows. Below, read on to meet the cast of Weak Hero Class 2. (If you're looking for a breakdown of Weak Hero Class 2's ending, we've got you covered.)

Park Ji-hoon as Yeon Si-eun

Park Ji-hoon, 25, returns to the series to continue the story of Yeon Si-eun, as the former model student attends the troubled Eunjang High School. Though he tries to stick to himself, still reeling from his guilt from the events of season 1, Si-eun eventually finds himself in the middle of a notorious gang's turf war.

Choi Min-yeong as Seo Jun-tae

At the start of Weak Hero Class 2, Jun-tae is the head lackey for bully Choi Hyo-man, who helps him steal the Eungang students's phones. However, after meeting Si-eun, Jun-tae decides to live a braver life.

Choi Min-yeong, 22, is best known among Netflix fans for playing Dae in the rom-com series XO, Kitty. The former child actor has appeared in several beloved K-dramas, including W: Two Worlds Apart, Strong Woman Do Bong-soon, Chicago Typewriter, Mr. Sunshine, and Itaewon Class, as well as the 2022 slice-of-life drama Twenty-Five Twenty-One.

Ryeoun as Park Hu-min, a.k.a. Baku

A teenage boy (Ryeo Un as Park Humin) raises a spray paint can while standing in a tiled room, in Weak Hero Class 2

Baku is the strongest kid at Eunjang and the head of the basketball club, whose reputation as a fighter precedes him. The good-natured leader has tried to make Eunjang a peaceful place, but his unfinished business with Union leader Na Baek-jin will eventually plunge the school back into violence.

Ryeoun, 26, made his acting debut in 2017 and got his start in romance and youth web series. He's best known for his main roles in the 2023 fantasy drama Twinkling Watermelon and the 2024 melodrama Namib. His other credits include Doctor Prisoner, 365: Repeat the Year, 18 Again, and The Secret Romantic Guesthouse.

Lee Min-jae as Go Hyeon-tak, a.k.a. Gotak

Lee Min-jae as Go Hyuntak, standing on a city rooftop, in Weak Hero Class 2

Gotak is Baku's teammate and loyal best friend. He also has a history with Baekjin and the Union. He's played by Lee Min-jae, 25, who rose to fame with his performance as Seo Geon-hu in the 2023 drama Crash Course in Romance. His other credits include While You Were Sleeping, Love All Play, The Golden Spoon, Cheer Up, and Kick Kick Kick Kick.

Bae Na-ra as Na Baek-jin

Na Baekjin is the leader of the Union, an illicit gang of students from local high schools. One of the best fighters in the area, the calculating student is determined to bring Eunjang and his childhood friend Baku under his control.

Bae Na-ra, 34, debuted as a musical actor in 2013; some of his stage productions have included Kinky Boots, Grease, West Side Story, and the recent Evil Dead The Musical. He made his K-drama debut with his standout role as an LGBTQ+ military deserter in the second season of the thriller K-drama D.P., which was followed by a supporting role in 2023's Evilive.

Lee Jun-young as Geum Seong-je

Geum Seong-je, Baek-jin's chaotic-evil lieutenant in the Union, is played by Lee Jun-young, 28. The prolific actor started his career as a K-pop idol, debuting in the group U-KISS in 2014. Since his acting debut in 2017, he has starred in movies and K-dramas including Imitation, D.P., Love and Leashes, Brave Citizen, Mask Girl, Badland Hunters, and The Impossible Heir. Weak Hero Class 2 is Lee's third Netflix K-drama of 2025 thus far, following the romances Melo Movie and When Life Gives You Tangerines.

Yu Su-bin as Choi Hyo-man

Choi Hyo-man, the Eunjang bully who confronted Si-eun in the Weak Hero Class 1 finale, returns in the new season. He's played by Yu Su-bin, 32, who's best known for playing Kim Ju-muk, the North Korean soldier obsessed with South Korean TV, in the romance K-drama Crash Landing on You. His other notable projects include Prison Playbook, Special Labor Inspector Jo, Start-Up, Lost, and D.P. season 2. Next month, he's set to return to Netflix in the rom-com K-drama Tastefully Yours.

Cho Jung-seok as Choi Chang-hee

Hospital Playlist star Cho Jung-seok, 44, appears in Class 2 as Choi Chang-hee, CEO of Cheongang, the adult gang that supervises The Union. The actor behind the menacing figure is one of South Korea's most popular actors, who started his career in musical theater and went on to star in hit movies including Architecture 101, The Face Reader, The Drug King, and Exit.

Last year, he made his singing debut with his chart-topping self-titled album after chronicling the project on the Netflix Korean reality show A-list to Playlist. His collaborators for the album included musicians like IU, Park Hyo-shin, and Cho's wife, Gummy. The couple were married in 2018 after five years of dating, and they welcomed their first child together, a daughter, in 2020.

Choi Hyun-wook as Ahn Su-ho

In Class 2, Si-eun regularly visits his best friend Su-ho, who's still in a coma after the events of the first season. Choi Hyun-wook, 23, portrays Su-ho. Since making his acting debut in 2019, Choi has skyrocketed to fame with fan-favorite roles in Racket Boys, Twenty-Five Twenty-One, Weak Hero Class 1, Twinkling Watermelon, and My Dearest Nemesis.

Hong Kyung as Oh Beom-seok

Also lingering in Si-eun's thoughts is Oh Beom-seok, the timid third member of the Weak Hero Class 1 trio. He's played by Hong Kyung, 29, a Baeksang Arts Award-winning actor, best known for his roles in the K-dramas School 2017, D.P., Lovers of the Red Sky, and Revenant.

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Quinci LeGardye is a Culture Writer at Marie Claire. She currently lives in her hometown of Los Angeles after periods living in NYC and Albuquerque, where she earned a Bachelor’s degree in English and Psychology from The University of New Mexico. In 2021, she joined Marie Claire as a contributor, becoming a full-time writer for the brand in 2024. She contributes day-to-day-content covering television, movies, books, and pop culture in general. She has also written features, profiles, recaps, personal essays, and cultural criticism for outlets including Harper’s Bazaar, Elle, HuffPost, Teen Vogue, Vulture, The A.V. Club, Catapult, and others. When she isn't writing or checking Twitter way too often, you can find her watching the latest K-drama, or giving a concert performance in her car.