Kim Ha-na discovers she is the first fiancée of Chun Namjoo, the cursed heir whose fiancées keep dying mysteriously. On the day of her engagement party, she learns from a romance novel prediction that she will be poisoned and die that night. Determined to stop the fatal event, Ha-na desperately tries to cancel the party but faces pressure to proceed, including being forced to wear an expensive dress and attend. Amid her fear and frustration, she pins hope on Park Woolin, a powerful figure known as 'the tyrant,' who she believes can protect her and possibly save her from the deadly curse.