
As the episodes of SBS's 'Brilliant New World' progressed, viewers were increasingly shocked by the unpredictable dialogue of the character Cha Se-gye. His self-absorbed, direct remarks and cheeky expressions flowed continuously, yet they were perfectly 'Cha Se-gye-ified' through Heo Nam-jun's performance. Many viewers expressed admiration for the actors' skills, noting how each line became a topic of discussion online. Even expressions that could easily come off as excessive or overly sentimental were delivered in a way that evoked laughter and excitement. Heo Nam-jun played a significant role in making the character's bold charm believable to the audience.
"I was worried. I wondered if I could do it well. I thought that in a romantic comedy, the acting needed to be more delicate. There aren't any dramatic, stimulating points to showcase, so I had a lot of concerns. In the beginning, I asked many questions. Even when reading the same script, everyone imagines it differently, so I think I was constantly aligning with the director during the early to mid-stages of production."
From the moment he read the script, Cha Se-gye's way of speaking was anything but ordinary. The constant stream of self-absorbed, direct expressions and cheeky jokes was challenging, but Heo Nam-jun soon felt a desire to tackle this challenge creatively.
"I didn’t feel like it was a disaster from the start. I just wondered how I would pull it off. When I hit a snag while reading the script, I tend to look for another direction. I did take a deep breath, but the thought that it would be fun to pull this off came to me immediately. The writer had naturally woven it into the text from the beginning, and the scenes unfolding in the drama were also unusual. As I continued watching, it started to feel natural at some point."

Cha Se-gye's cheeky tone was not entirely unfamiliar to Heo Nam-jun. He approached the character by recalling the ways of speaking he found attractive in people around him.
"When I meet friends, each has their own way of speaking. Some friends speak in a refined and relaxed manner, while others joke around cheekily. I find those people naturally charming, and I’ve often synced with their way of speaking. So, I didn’t have much resistance to using Cha Se-gye's cheeky tone. The ways of speaking I’ve learned over time helped me a lot."
One lingering concern was whether a romantic male lead could be so direct. Heo Nam-jun grappled with how to express the high level of self-love in Cha Se-gye's dialogue. He credited the writer's design as the reason the character's bold lines gained strength in the latter half of the series.
"I pondered how to express the high self-love statements and to what degree of tone and intensity they should be delivered. I wondered if it was too direct for a romantic male lead. However, I think the writer's meticulous design allowed for bolder lines to emerge as the story progressed. When the narrative seemed to deepen, it would lighten up, and when it felt blocked, it would refreshingly open up again. Watching the lines and scenes of characters like Se-ri and Kim Du-han made me think that if I could implement them well, it would be fun."
Initially, Heo Nam-jun approached Cha Se-gye's emotions and actions with a rational analysis. He repeatedly read the script to find his role within the scenes and constantly checked with the director on whether his approach was correct. However, as filming progressed into the middle of the series, moments arose where his heart reacted before his mind did.
"When I read the script, I try to view it as rationally as possible, rather than instinctively. If I get too caught up in one emotion, I can’t help but lean towards that. At first, I read my role and thought about what I needed to deliver. On set, I would think, 'What should I do here?' and ask the director if this tone was right. But at some point, there were instances where my heart moved before my head. I felt immersed and believed in Cha Se-gye."

The actor's efforts paid off with the show's success. The final episode of 'Brilliant New World,' which aired on June 20, recorded a nationwide and metropolitan area viewership rating of 11.8%. The peak rating soared to 14.1%, setting a new record for the series and finishing as the top-rated mini-series in its time slot and for the week.
"I'm feeling good because the show has done well. I enjoyed watching it, and I'm glad that viewers showed a lot of interest. I have my next project lined up, so I can’t go out much, but I feel like more people are recognizing me on set. I can sense the show's popularity through the messages I receive from people around me."
Heo Nam-jun was particularly impressed by certain scenes when watching the completed broadcast. The endings of episodes three and nine stood out to him. The combination of his immersed performance with direction and music added unexpected strength to those moments.
"I really liked the endings of episodes three and nine. Especially the scene where the contract is signed, the buildup from earlier comes together, and the music enhances the emotions. It might be a cliché situation, but I was deeply immersed in my performance. Watching the edited broadcast, it felt fresh, and with the added music, it became even more impressive. Even though it was a scene I acted in, I thought it was great to watch."

Heo Nam-jun expressed his fondness for his eyes and jaw as an actor. He believes that his eyes convey both good and evil, allowing him to portray characters with different personalities.
"I like my eyes and jaw. I think they are advantageous when acting. I believe my eyes express both good and evil. I’m grateful that I can portray both sides."
'Brilliant New World' will be remembered not only for its success but also for the positive atmosphere among the cast and crew. Even when facing physical limits, they refrained from hurtful words and gave their best in their respective roles, making the success of the project even more rewarding.
"Like all projects, the atmosphere on set was really good this time. Everyone faces physical limits while working. Still, we avoided saying hurtful things to each other and exchanged good and warm words. Each person did their best in their position. Of course, a good atmosphere on set doesn’t guarantee a successful project. But I’m really happy that the project turned out well. I think it’s a work that has changed my life a bit more."

Following 'Brilliant New World,' Heo Nam-jun will meet viewers again in his next project, tvN's 'Whale Star.' As it is based on a popular webtoon, he carries the expectations and pressures of the original fans. He is focusing on finding the intersection between the character's charm and his own, rather than simply replicating the original work.
"Every project comes with pressure. There is some this time as well, but I’m trying to eliminate it as much as possible. I think trying to replicate the webtoon exactly could be one-dimensional. It’s impossible to meet all the expectations of the original fans. While I want to enhance my performance without damaging the original work, it’s not easy. I’m working hard to find the intersection between the character's charm and my own. I read the webtoon slowly and focused on understanding the text. Just as I did my best in 'Brilliant New World,' I will work hard in my next project too."
* This article has been translated by AI.
Copyright ⓒ Aju Press All rights reserved.

