Beginnings Kim began his acting career on television with a minor role in the 1999
KBS youth drama
School 1. Four years later, he passed the 2003 Talent Audition conducted annually by
MBC, and appeared in various minor roles on the network's shows, such as
Be Strong, Geum-soon!. During this time, he was using the
stage name Lee Han, which he made up to avoid confusion with
Kang Nam-gil, another Korean actor with a similar name, and to give himself a more sophisticated image. In the following years he took on more supporting roles in
television dramas, among them
Goodbye Solo,
Lovers, and
When Spring Comes. Kim debuted on the big-screen in 2004 gangster movie
Low life. In 2006, he made the bold decision to portray a homosexual character in the controversial
queer indie No Regret in a role which included several gay sex scenes. The film was critically praised and traveled the film festival circuit, being shown among others in the Panorama section of the 57th
Berlin Film Festival. He was then cast in 2008's
Public Enemy Returns, where he worked with the actor
Jung Jae-young. Kim had stated in interviews that
Jung Jae-young, who attended the same high school he did, had been his role model as an actor. Upon the influence of the film's director
Kang Woo-suk (but against the advice of his agent and manager Later that year, he played his first leading role in a major commercial film,
Portrait of a Beauty. Though his co-star
Kim Min-sun garnered most of the attention for the erotic
costume drama, Kim's strong performance did not go unnoticed.
Breakthrough and rising popularity In 2009, Kim was cast as one of the supporting characters in the historical drama
Queen Seondeok, in a role that would soon change his life. It became one of the highest-rated TV series of that year (reaching a peak of over 40%), and Kim became a household name and the series' breakout star. For his portrayal of the playful but tragic
Bidam, Kim said he was inspired by comic book characters such as Han Bi-kwang in
Ruler of the Land,
Miyamoto Musashi in
Vagabond, and
Kang Baek-ho in
Slam Dunk. The writers rewrote the script to respond to Bidam's popularity with the viewing audience, giving the character more screen time and emphasizing his romance with the titular
Seondeok (despite the incredible historical inaccuracy), until there were two main male leads in the series. A horse-riding-related injury on set, and a brief hospitalization due to
H1N1 flu, were minor negatives compared to the impact the series had on Kim's career. He won several awards for his performance, gained more local and international fans, received advertisement offers, and was flooded with film and TV scripts. Another side benefit of Kim's popularity resulting from the
Seondeok was the theatrical release in 2010 of his
indie Lovers Vanished, a relationship drama which the director described as a "Korean
Leaving Las Vegas." In 2010 he played an
antihero lead role in
Bad Guy, a dark melodrama about revenge, ambition, and fatal love. But while still in the middle of filming, Kim received his draft notice for
mandatory military service. He tried to ask for deferment in order to wrap up the shoot for the series, but it was not granted. Kim shot as much as he could (his scenes were reduced, and a
body double was also used) then entered the army two days later on July 15, 2010. He received four weeks of basic training at
Nonsan, and served for two years as a public service worker. Following his discharge from the army in 2012, Kim produced the film
Ensemble, a music
mockumentary about a group of classical musicians who form a group and take to the streets to perform outside their usual concert halls, showing their youthful passion in making music accessible. It premiered at the
Jecheon International Music & Film Festival. He was also one of four celebrities in 2013 who directed a
short film using
smartphone Samsung Galaxy S4 with the theme "Meet a Life Companion"; his short
Hello, Mom depicted the love between a mother and her daughter, and evoked the warm feeling of an
analog film. This was followed by the 2014 period adventure film
The Pirates, which reunited him with
Shark costar
Son Ye-jin. In 2013 Kim starred in the revenge TV series
Shark (also known as ''Don't Look Back
), from the makers of Resurrection and The Devil. He next starred opposite award-winning actress Jeon Do-yeon in the 2015 thriller The Shameless; Kim played a detective who falls for the girlfriend of the murderer he is investigating. The Shameless had its world premiere at 2015 Cannes Film Festival in the Un Certain Regard section. Nam Gil was next cast as powerful nobleman Heungseon Daewongun whose concubine takes up pansori in the period film The Sound of a Flower''.
Critical and commercial success In 2016, Kim starred in disaster blockbuster
Pandora portraying the aftermath of an explosion in a nuclear plant.
Pandora premiered internationally at the International Film Festival and Awards Macao (IFFAM), receiving standing ovation. In 2017 Kim starred in the action thriller
Memoir of a Murderer and romance drama film
One Day. In 2019, Kim starred in the comedy film
The Odd Family: Zombie On Sale. In 2020, Kim starred in the horror film
The Closet. In 2017, he starred in the time-slip medical drama
Live Up to Your Name. In 2019 he headlined the comedy crime drama
The Fiery Priest as a hot tempered priest. It was the first drama to air on Fridays and Saturdays on
SBS and was well received by viewers, seeing a rapid rise in ratings and ending at a peak of 22%. Kim earned a Best Actor nomination at the
55th Baeksang Arts Awards, and went on to win eight awards for his performance including the Grand Prize (Daesang) at the
2019 SBS Drama Awards. excluding Kim as a special appearance in the drama, SBS's
One the Woman in which he appeared to support one of his previous co-star
Lee Ha-nee. In 2025, Kim starred in Netflix's
action thriller television series
Trigger wherein he portrayed Lee Do, a former military sniper turned police officer investigating the illegal firearms trade. In the same year, Kim starred in the
neo-noir crime thriller film Nocturnal marking the second time he acted alongside
Ha Jung-woo working with the 2020 film
The Closet. == Other ventures ==