A rumor about how Prince Hwan has been cursed by a ghost has spread throughout the country. He has a dark secret he can't tell anyone. People who are trying to get Hwan dethroned prepare a trap and Hwan must stand against them. Meanwhile, the one who killed Hwan's Master comes to see him of her own free will.

After facing a crisis at the hunting grounds, Hwan finds himself in an unbelievable situation. Jae-yi. claims that she's innocent and blames Hwan for the death of her family. Hwan is confused when he finds out Jae-yi knows about his secret. Meanwhile, Jae-yi's servant disguises herself as a man to learn from the mad scientist, Kim Myeong-jin.

Hwan can't trust Jae Yi and tells her to come find him in the East Palace one her own. To get there, Jae Yi turns herself into a eunuch. Meanwhile, Seong On is shock to learn that his father might have something to do with the written prayer incident.