Kim Won-seok initially entered the entertainment industry as a director before transitioning to become a writer. He started as part of directing department of the film '''' in 1999. Followed by assistant director for two
Ryoo Seung-wan's film
Die Bad and
The City of Violence. In 2008, he made his debut as a writer with the script adaptation of the film ''''. In 2009, Kim co-wrote and co-directed
Kwak Kyung-taek's drama
Friend, Our Legend. It is a
remake / TV
adaptation of
Kwak Kyung-taek's own 2001 box-office hit film
Friend. A year later, Kim returned with his new drama
Man to Man, which made history as the first South Korean television series to be simulcast on both television and
Netflix.
Man to Man tells the story of a mysterious agent who becomes a bodyguard for a famous Korean star and deals with secretive people around him. The drama presents the thrilling adventures of these secret agents in different exciting ways.'' Filming began on October 17, 2016, and ended on March 6, 2017, taking place in
Seoul,
South Korea and
Budapest,
Hungary. Notably, the first episode featured a parody of a famous scene from ''
Descendants of the Sun',
and two actors from the drama, David Lee McInnis and Song Joong-ki, made cameo appearances.' Kim took a hiatus for several years before returning in 2023 with
Payback, a revenge drama that revolves around the characters Eun-yong (played by
Lee Sun-kyun), a skilled financial merchant, and Jun-kyung (
Moon Chae-won), a legal expert. Together, they confront a formidable cartel. The drama has achieved a noteworthy viewership rating of approximately 10%. == Filmography ==