After waking up late, flunking her pop quiz, embarrassing herself on numerous occasions, and starting a fire in her home economics class, high school student Makoto Konno figures she's just having one of those days. And just when she thinks she's made it through, the brakes on her bike malfunction putting her on a collision course with a speeding train. The life-ending accident would have been the perfect end to the worst day ever, but the strangest thing happens-she leaps backwards in time. After unlocking her new ability, Makoto does what any teenager would do. She re-takes tests, corrects embarrassing situations, and sleeps in as late as she wants, never thinking that her carefree time travelling could have a negative effect on the people she cares about. By the time she realizes the damage she's done, she only has a few leaps left to make things right.