Young-eun is a very talented singer at her school who has a very unique voice but may be the same as someone else. One night staying to practice her singing at school she gets ready to leave and ends up being murdered in front of the elevator. Young-eun wakes up the next day and still thinks that she is alive and walks around the school like it was a normal school day. After figuring out she is dead and is a ghost, Young-eun and Sun-min (Young-eun's best friend) try to figure out why she was murdered and who did it. Cho-ah, another girl from the school starts chatting with Sun-min and tells her she should let Young-eun go and rest in peace, the only way to do that is to forget about her and move on.