A tale of a flower that became a king. For many years, Queen Gonghye has struggled to produce a son as a way to protect the Royal Family and from the evil machinations of the concubine, Royal Noble Consort Hye. However, a fifth daughter is imparted upon her by the heavens after her only son dies in childbirth. The queen decides to masquerade the princess as the deceased prince in order for them and her family to survive. Will Yi Yong be able to live the rest of her life as a man or will her own desires to live as a female succumb her and lead to the ruin of her mother's family? And what happens when love decides to enter the picture?