"You are the finest, loveliest, tenderest, and most beautiful person I have ever known- and even that is an understatement." - F. Scott Fitzgerald . . . . . . [ ATEEZ's Park Seonghwa ]

When mental institution nurse Young Hyejin suddenly disappears and convicted serial killer Choi San, a patient on the ward Hyejin works in goes missing, it is up to Hyejin's co-worker and close friend Park Seonghwa to save her, but things are much worse than it seems...