Tells the story of Lin, a freshman at Sheng Hua High School. She is a pretty and pretty girl, although she is a bit quiet and introverted, but her friends like Xu (Lin Yi), Song (Shen Yue) and Jiang Wu (Wang Jia Hui) want to get to know her. But Xiang doesn’t want to know anyone. and don’t want to be friends with anyone Because there is a strange disease that every Monday you will forget about the past week. However, Xu The last student of the class was not discouraged. Actively acting intimate with and believes that one day she will remember him without forgetting The three of them worked together to find a way for to remember them every Monday. But what they don’t know is that behind this strange disease there is a secret. What’s the secret?