Wrongly killed by her fiancé, Minjeong sells her soul to Si-an, the devil, to turn back time. Getting back to the past of a week ago, her revenge to dig up the conspiracy begins. In a past life, a destined love of Si-an and Minjeong ended in tragedy, and reuniting as the devil and the dead in a contract relationship for revenge in 100 years, they reaffirm their love for each other.
