Choi Hyeon-gyeol is trapped in a hellish temporal prison. Every time the clock strikes midnight on the 15th, he is ripped back to the start of the previous day. Forced to repeat the exact same university assignments twenty times over, his sanity has worn dangerously thin. Pushed to his absolute breaking point by the monotony, Hyeon-gyeol decides to abandon all caution and indulge in a wild, impulsive escape from his scripted life. This leads him to an unexpected, heated one-night stand with his fellow classmate, Lim Yeonjeong. He falls asleep expecting to wake up to the same familiar nightmare once again. However, against all odds, the loop finally breaks. For the first time in what feels like an eternity, Hyeon-gyeol opens his eyes to the fresh, uncharted morning of the 15th… with Yeonjeong right beside him