Who was the director of a movie where Oh Jung-se played an onscreen supporting role?
Oh Jung-se:  Oh began his career in theater, and has since appeared in many onscreen supporting roles over the years, notably in "Petty Romance" (2010), "Couples" (2011), "As One" (2012), "A Millionaire On the Run" (2012), and "Running Man" (2013). As One (film):  Director Moon Hyun-sung used the foundation of true events to tell the story of a team that united a divided nation for the first time in its painful history.
Moon Hyun-sung