Kang Sang Hee has been crushing on her best friend's brother, Jung Yong Hwa, for years now. Problem is, Yong Hwa still sees Sang Hee as a little girl. On Sang Hee's 15th birthday, she finds a book of spells that was hidden in her dead mother's box. Curious, she skims through it & finds a spell that might be useful to her. The spell is to become a 23 year old woman. She does the spell, unaware of it's consequences, a spirit will take over her body at midnight for one hour to create chaos and