Yoo Ah-in (born Uhm Hong-shik on October 6, 1986) is a South Korean actor. He rose to fame in television series Sungkyunkwan Scandal (2010), and became best known for his leading roles in coming-of-age film Punch (2011), melodrama Secret Love Affair (2014), action blockbuster Veteran (2015) and period drama Six Flying Dragons (2015).