Clara's best friend dies a day after they confess their feelings minutes before they start their first date. Heartbroken she comes across a man who claims to help her. He tells her that there is a way of getting Min-Joon back which is to go back in time. She agrees telling herself that she will convince Min-Joon to go to another hotel for the date. The only problem is that she is not sent back on the day they confessed their feelings;she is sent to when Min-Joon was in highschool in South Korea. But that isn't the only change that happens.