The Duo (Hangul: 짝패; RR: Jjakpae) is a 2011 South Korean historical drama series, starring Chun Jung-myung, Lee Sang-yoon, Han Ji-hye and Seo Hyun-jin. It aired on MBC from February 7 to May 24, 2011 on Mondays and Tuesdays at 21:55 for 32 episodes.Filmed at MBC Dramia in Gyeonggi Province, the series examines how class determines fate during the Joseon era through two men who swap lives. Switched at birth, Chun-doong and Gwi-dong grow up living each other's lives.