Plot Summary

In the mystical kingdom of Daeho, a forbidden spell known as the alchemy of souls allows spirits to move between bodies. After the assassin Nak-su is mortally wounded, she uses the spell to survive inside the weak body of Mu-deok, a servant girl. Concealing her identity, she becomes entangled with Jang Uk, a young noble whose magical abilities are sealed, and the two set out on a journey shaped by hidden powers, political rivalries, and shifting loyalties.