Hong-Rang (Lee Jae-Wook) was born into a wealthy family and was the successor to a large merchants' association in Joseon, but he suddenly disappeared at age 8. His older stepsister Jae-Yi (Jo Bo-Ah) has never given up hope on finding him. His arrogant mother, Min Yeon-Ui (Uhm Ji-Won), the most powerful figure in the merchants' association, has experienced difficult times since his disappearance. After 12 years, Hong-Rang, now age 20, returns, but he remembers nothing prior to his disappearance and also carries a secret. Jae-Yi suspects that Hong-Rang is not the real Hong-Rang and she becomes attracted to him.
—AsianWiki