Miyu and Shuya are high school students. They have dated for 2 years. Miyu and Shuya have a promise that no matter what, they will watch a movie together on the first day of each new month. When Miyu and Shuya are on their way to the movie theater, Shuya suddenly cancels their date. Shuya seems like he is hiding something and he acts nervous. Later, Miyu goes to the place where she is supposed to meet Shuya, but she witnesses Shuya getting into a car accident. She panics, but when she wakes up she finds herself on the morning of the accident. Miyu keeps waking up on the day when Shuya got into an accident.
Jung Yeol and Na Ra fell in love with each other and got married. During their marriage, they have grown to hate each other due to their personality differences. They decide to get a divorce. A month later, their divorce will be finalized. But, on the day that they applied for a divorce, they get into a car accident. When they wake up at the hospital, they have both lost their memories and do not remember each other.
