Park Ji-hoon Reflects on “Weak Hero Class 2”: “Yeon Si-eun is My Most Beloved Role”

Among Korea’s many coming-of-age dramas, Weak Hero Class stands out for its gripping portrayal of school violence and teenage struggles. Directed by Han Jun-hee and Yoo Soo-min, the series follows top student Yeon Si-eun (Park Ji-hoon) as he forms deep bonds while facing brutal challenges.

Weak Hero Class 2, a Netflix original released on April 25, 2025, quickly topped the Global TOP 10 Non-English Series with 61 million views in three days and ranked in 63 countries, including South Korea, France, and Brazil.

Park Ji-hoon, whose intense performance anchors the series, has shed his idol image for a more mature, stoic presence. In a recent interview, his thoughtful tone and serious demeanor mirrored his character, earning praise for his evolution as an actor and fueling anticipation for his future roles.

What motivated you to join Weak Hero Class 2?

Director Yoo Soo-min told me he felt guilty for ending Weak Hero Class 1 with Si-eun transferring to Eunjang High. He suggested, “What if Si-eun makes new friends and continues his story?” Si-eun is my favorite character in my filmography, so I immediately agreed to join Weak Hero Class 2. In Weak Hero Class 1, Si-eun lost a friend and everything else, ending with him breaking a glass window, which was emotionally draining for me. After filming, I sat in a corner of the set and sobbed. Si-eun is a character I deeply empathize with. Weak Hero Class 2 ending on a happier note felt so rewarding.

The relationships surrounding Si-eun in Weak Hero Class 2, especially with Geum Seong-je (played by Lee Jun-young), drew attention.

Lee Jun-young is a senior I’d normally bow deeply to at music shows, but he approached me warmly, treating me like a close friend and joking around. We bonded over shared hobbies, practiced dance together, and filmed videos while vibing to music. There’s a rooftop fight scene between Si-eun and Seong-je that he loved, and fans have called it a favorite, even from the webtoon. I wonder why it’s so popular—maybe it’s the cat-like Seong-je clashing with the tiger-like Si-eun. I’m curious too.

Director Yoo said you shed tears after the cast and crew watched Weak Hero Class 2 together, though you never showed that during filming.

I haven’t fully let go of Si-eun yet; he’s still in my heart. I cried because I was relieved to see Si-eun smile. Unlike the rage-filled ending of Weak Hero Class 1, Weak Hero Class 2 gave me a sense of relief. I felt the cast and crew’s shared goal, and as someone who played Si-eun, I felt both pity and hope for his growth. Those complex emotions brought tears. Watching Weak Hero Class 1 again after Weak Hero Class 2’s release still makes me emotional. Playing Si-eun has impacted me deeply.

Why is Si-eun your favorite character?

He resembles me. I feel for him and find him pitiable, which makes him my favorite. His lonely moments mirror my own. Balancing acting and school meant I didn’t have many friends growing up, and few reached out to me. As a child actor, I relied heavily on my parents, so I understand Si-eun’s solitude and why he feels at ease alone. That’s why I wanted him to make friends.

Among the Baku Family in Weak Hero Class 2, who resonates with you most?

Park Hu-min (Ryeoun), Seo Jun-tae (Choi Min-young), and Go Hyun-tak (Lee Min-jae) all have unique charms and inner and outer strength. It’s hard to choose just one.

How did you differentiate Si-eun in Weak Hero Class 2?

I wanted Si-eun’s gaze and fighting to convey, “Let’s stop this childish, tiresome nonsense.” I aimed to show his reluctance to fight through his eyes and expressions. Preparing for Weak Hero Class 2, I focused on how Si-eun and his friends would resolve conflicts with a major figure like Na Baek-jin, rather than just Si-eun’s character alone.

What’s a memorable filming moment from Weak Hero Class 2?

There’s a scene where Si-eun feels at ease for the first time. At a museum, sitting in a row with Hu-min, Jun-tae, and Hyun-tak, eating convenience store food, Hu-min jokes about getting girls’ numbers. Si-eun’s face softens with a subtle, almost-smiling expression. I love that moment of calm. I struggled with how much to smile to show Si-eun’s comfort without overdoing it, and I think it came out well.

Si-eun’s gaze in both seasons powerfully conveys the harsh realities, frustrations, friendships, and recovery of teens. Are there scenes you’re proud of?

No actor, even seniors, can say a project was perfect. I have regrets and moments where I wonder, “What if I’d done it differently?” or “Should I have held back more?” I’m grateful for the praise, but as the actor, I’m never fully satisfied.

With Weak Hero Class 1 gaining global popularity on Netflix after Wavve, and Weak Hero Class 2 also seeing strong international response, why do you think the series resonates worldwide?

I’m grateful for the love for Si-eun. I think audiences connect with a young boy’s growing pains, the thrilling action, and the bromance chemistry. Fans love Si-eun and Jun-tae’s dynamic, or the unique, adversarial chemistry between Si-eun and Seong-je. In Weak Hero Class 1, the bromance between Si-eun and Su-ho was a fan favorite. The series’ strength lies in its bromance.

Seong-je’s line “Romantic Pass” became iconic. What kind of “pass” would you give Si-eun?

Si-eun is far from romantic, but I’d praise him for opening up to friends. Despite his trauma, he didn’t close himself off, which made Weak Hero Class 2 possible. I’d commend him for keeping his heart open. “Romantic Pass” perfectly captures Seong-je’s playful, fight-loving nature. When we watched the series together before release, everyone gasped at that line—it defines the character.

How did you interpret the Baku Family’s charm?

From Si-eun’s perspective, Hu-min feels similar to Su-ho, drawing him in. Jun-tae likely saw Si-eun and wanted to change. Si-eun has a magnetic pull, influencing those around him. The cast’s chemistry was amazing, and everyone’s immersion in their roles created great energy.

The large-scale fight scenes in the latter half must have been tough. Any injuries?

In Weak Hero Class 2, Si-eun’s resilience grew. From Weak Hero Class 1’s unavoidable fights, he developed skills and know-how. As a character and action hero, he evolved. The big fight at Wausan took over two weeks to film. Si-eun joins late, and it was fun and safe to shoot.

What are the strengths of directors Yoo Soo-min and Han Jun-hee?

They were incredibly supportive, valuing my input and understanding my perspective on Si-eun, even when it differed from theirs. They’d run around directing and always asked for my thoughts post-take. Their openness made working with them amazing.

Si-eun looked heavier on-screen, but you’re quite slim. Did you diet post-filming?

I focused on portraying Si-eun, not my appearance. Obsessing over looks hinders immersion. I didn’t skip meals or adjust my weight for safety during action scenes. I just wanted viewers to see Si-eun as he is.

Si-eun’s gaze is often cited as the series’ highlight. How did you achieve it?

Expressing through eyes alone is tough, especially with minimal dialogue, but I’m glad viewers connected with Si-eun’s anger and sadness. I studied a lot but found overtrying led to overacting. Instead, I immersed myself in Si-eun’s emotions—feeling cold or consumed by rage—and focused on those raw feelings without specific techniques.

In the end, Weak Hero Class 2 is more than just a brutal school action drama—it’s a deeply emotional exploration of friendship, growth, and resilience. As Park Ji-hoon continues to evolve as an actor through the character of Yeon Si-eun, audiences are left not only with heart-pounding scenes but also a lingering sense of empathy and reflection.