Tin is a 29-year-old 3rd year emergency medicine resident who has to face a chaotic scene in the emergency room every day. One day after he wakes up in the dining room, a university student severely injured by an accident is brought into the ER. Unfortunately, Tin can't save this patient's life. That night he falls asleep in the same room. He wakes up on the 18th and later realizes that he is stuck in a time loop, reliving the same day again and again. And it seems that the only way to help him escape from this circle is to save that student's life.