The troubled Crown Prince Sajo Hyeon (Park Ji Hoon) has a dark secret: he has a charming but flawed alter ego named Ak Hee, who works in an unassuming downtown store. Sparks fly when the Prince meets Yeon Wol (Hong Ye Ji), a vengeful descendant of a fallen royal family. She’s on a mission to kill the King, but loses her memory in a trap and ends up as the Prince’s concubine. Will she recover her memories and carry out her deadly mission? And could she help heal – and find love with – the tormented prince?