Roo Da's been living an ordinary life, trying her best not to stand out because she knew nothing good ever comes out of it. One day, she faces the biggest obstacle of her lifetime and is forced to save everyone from reliving the same day over and over again. However, in order to do so, she must reform her horrible boss, Jin Sang, into a decent human being. While doing so, she saves her coworkers from danger, fights against corruption, and becomes a hero she never intended to be. For everyone's sake, she must break the endless cycle of time loop and make tomorrow come.