Hwayeon Ryu, without knowing the cause, falls into a coma at the age of six. Then after 12 long years of her father, Chung Ryu's persistent attempts, she finally opens her eyes. As she wakens from her prolonged sleep, she realizes she not only has her memories but has the memories of someone else's life, Yeonu Lee. Though startled at first, as time passes, she manages to adjust to her new life. Then one day, in hope to have lunch with her father, she pays a visit to the palace. But she ends up taking the wrong turn and finds herself in front of the notorious beast, crown prince Muyeong...