Taeyang Group is the largest conglomerate in South Korea but the Choi family, who runs Taeyang, has supposedly been under a hundred-year-curse - the first bride of the eldest son will always die. Choi Kang-joo, the current heir to Taeyang Group, had been arranged to marry heiress Jang Yi-gyeong when she suddenly disappears. The Jang family, desperate to maintain the engagement, finds a poor village girl, Na Doo-rim, who looks exactly like Yi-gyeong, and convinces her to masquerade as the missing heiress in exchange for a sizeable sum of money. Doo-rim's sweet and sunny personality captivates Kang-joo but he has no idea about her hidden identity nor about his family's hundred-year-curse. What will happen when these two people end up falling in love with each other?