Kim Woo-bin, like many others, had never known that a job such as a martial arts officer really existed before taking on the character in Netflix's Korean original action movie "Officer Black Belt."

"I have to admit, I had never heard of this profession before receiving the script. In a way, that made the role even more intriguing to me," the actor said during a group interview with local reporters in Seoul on Thursday.

Kim said he was pleased to learn that director Kim Joo-hwan aimed to raise awareness about the profession during their first meeting and felt an immediate connection with the director on this shared goal.

"I learned about everyday heroes I hadn't known before, and I realized that I've been living a safer and happier life thanks to them," he said. "I wanted to convey this feeling to the viewers."

Actor Kim Woo-bin is shown in this photo provided by Netflix on Sept. 19, 2024. (PHOTO NOT FOR SALE) (Yonhap) 

The actor plays Lee Jung-do, a character with a simple goal in life: to live each day happily. Skilled in martial arts, such as taekwondo, judo and kendo, and holding the highest-level belts, he is an ordinary young man who enjoys playing video games with friends and helping out at his father's chicken restaurant as a delivery person.

One day, he unexpectedly steps in to assist a martial arts officer struggling to subdue a violent parolee. This incident opens up a new chapter in his life: he is hired as a temporary martial arts officer and begins working alongside probation officer Kim Sun-min (Kim Sung-kyun).

Released Friday, the movie debuted at No. 1 on Netflix's non-English movies chart, garnering 8.3 million views in the week ending Sunday.

The actor expressed deep gratitude for the largely positive response to the movie. One comment, in particular, stood out to him. "A viewer mentioned they would gladly pay to watch the film in a cinema," he shared. "That really made my day."

What touched the actor the most was seeing how his character's emotional and mental journey resonated with audiences. "It's truly special when viewers connect with the character's growth as I did," he said.

Despite his success, the 35-year-old actor humbly admitted he's still learning to gauge audience reactions. "With each project, it's always a toss-up whether viewers will like it or not," Kim said. "I start every role with a mix of anticipation and nervous energy."

That said, he added, "I feel relieved that the audience seems to connect with what I felt while working on the film," a sign, he said, of validation for the hard work and emotional investment he put into the project.

A captured screen from the Netflix chart on Sept. 19, 2024, is shown in this image. (PHOTO NOT FOR SALE) (Yonhap)

Outside of a movie set, he aims to live each day to the fullest, much like Jung-do does in the film. This perspective was reinforced after Kim's battle with a rare form of throat cancer. Diagnosed in 2017 and fully recovered by 2019, the actor found that this shared life philosophy helped him better understand and portray his character.

"I used to live in the future until a few years ago. I would tell myself, 'In ten years, I'll be a better actor so I should worker harder today,' or 'Next week, I will have a better physique so I should work out more today.'"

While he appreciates that these experiences have helped shape who he is today, he regretted not appreciating those everyday moments more.

"I felt regretful for being too hard on myself. I now have a new perspective and approach to life," he said. "One thing I make sure to do every day is to look into the eyes of the person I am talking to. By focusing on these interactions, I feel I am living each moment more fully."

 A still from Netflix's Korean original movie "Officer Black Belt" is shown in this image provided by the global streaming service. (PHOTO NOT FOR SALE) (Yonhap)

Written by Woo Jae-yeon