Kim Yoon-seok (born January 21, 1968) is a South Korean actor. Kim's theater background first led him to be cast in minor roles on film and television. His breakout role came as the villain in gambling film Tazza: The High Rollers (2006), but it was his performance as a pimp and ex-cop in surprise hit The Chaser (2008) that brought him acting awards and stardom in his forties. Kim has since become an acclaimed leading actor in Korean cinema, in films such as Running Turtle (2009), The Yellow Sea (2010), Punch (2011), and The Thieves (2012).
Kim Yoon-seok was trained on stage as a member of the renowned Theater Yeonwoo Company (Yeonwoo Mudae), and he made his acting debut in 1988 with A Streetcar Named Desire. After many years in theater, he began acting in film and television late in his career, at first appearing in minor roles. Then in 2006, Kim had his breakthrough in Choi Dong-hoon's Tazza: The High Rollers, with audiences praising his performance in the supporting role as ruthless gambler Agwi (meaning "starving demon" in Buddhism). A leading role followed in 2008 with The Chaser, directed by Na Hong-jin. He successfully portrayed the morally ambiguous character of a retired-cop-turned-pimp hunting down a serial killer. The thriller was a critical and commercial hit, and Kim became a major player in the Korean film industry. He transitioned from one of the finest character actors in the industry into a popular leading actor: Kim played a middle-aged man following his lifelong dream to play in a rock band in The Happy Life, a rural detective trying to capture a legendary prison breaker in Running Turtle, and a rival Taoist wizard in Jeon Woo-chi. In 2010 Kim reunited with The Chaser costar Ha Jung-woo in Na's ambitious sophomore film The Yellow Sea. The year after, Punch became the third highest grossing film of 2011, in which Kim portrayed an ill-tempered teacher giving courage to a youth from the slums. Kim once again triumphed in 2012, as his heist movieThe Thieves became the second best-selling Korean film of all time. He continued working with Korea's leading directors in 2013, in Im Soon-rye's South Bound, and Jang Joon-hwan's Hwayi: A Monster Boy.