Marine Boy (Korean: 마린보이; RR: Marin Boi) is a 2009 South Korean action thriller film. The feature film debut of writer and director Yoon Jong-seok, it stars Kim Kang-woo, Cho Jae-hyun and Park Si-yeon in the lead roles. Marine Boy is the story of a former national swimmer who finds himself in debt, and out of desperation is employed as a mule by a gangster boss, smuggling drugs by sea. Yoon regarded the film's title as a unique point, saying, "There is something beguiling about its duality, how these criminals are called something that romantically calls to mind the popular cartoon Marine Boy or the star swimmer Park Tae-Hwan".