Twinkle, twinkle, bright star How did Lin Beixing go back to the past and what happened?

In the play, Lin Beixing returned to the high school age of 18 by deleting the old mobile phone information, and got to know Zhang Wansen again. The reason why Zhang Wansen fell from the tower puzzled her, so she gradually discovered the secret hidden in Zhang Wansen's heart during her journey to save Zhang Wansen.

At the beginning, when Lin Beixing 18 was able to cross high school, she was very happy. She thought she could change herself here, but she always returned to real life because of the name Zhang Wansen, so she was full of curiosity about Zhang Wansen. She found that the reason why Zhang Wansen fell from the building was related to a red-haired man, so she always protected Zhang Wansen, but she didn't know that Zhang Wansen fell from the building to save him. So Lin Beixing began to get in touch with Zhang Wansen slowly. She studies and eats with Zhang Wansen. In the constant contact with Zhang Wansen, she had different feelings for Zhang Wansen.

Because she knew that Zhang Wansen would eventually fall from the tower, she always followed Zhang Wansen to protect him. Lin Beixing traveled through the past because of short messages, but she will return to real life for some reason. She used text messages to go back again and again, just to save Zhang Wansen. In the process of getting along with Zhang Wansen, Lin Beixing also liked Zhang Wansen, but when she found out that she liked Zhang Wansen, it was too late. She finally understood why Zhang Wansen fell off the tower during the college entrance examination. It turned out that everything was because he was protecting him. His love for himself is hidden in his heart, and he even keeps a diary. The diary is full of everything about Lin Beixing, about Zhang Wansen's wish to realize with Lin Beixing. In the end, Lin Beixing realized that every message she deleted was Zhang Shengsen's wish. That's why he went back to the past.

After Lin Beixing knew the reason why Zhang Wansen fell off the tower, he began to protect him. She hopes that Zhang Wansen can live. She used the last time to travel back to the past to make Zhang Wansen hate him and not protect her behind her back, lest Zhang Wansen get hurt. But how could Zhang Wansen not know? He still silently protects Lin Beixing.