While on his way to propose to his girlfriend, songwriter Lee-hyung (CHA Tae-hyun) gets into a car accident and wakes up in a high school girl’s body. Subsequently, he experiences the lives of a divorcee detective, perpetually single high school teacher, and a granny.
BJ Yagwang (Ryu Deok-Hwan) and PD Park (Jo Bok-Rae) broadcast a live stream themed around horror on AfreecaTV. They look for more provocative and fearful material for their program. One day, they receive a video which contains a female high school student disappearing.