Lin Si, a genius designer, and Bai Ze, the general manager of a consulting company, are a pair of long-distance lovers who spend less time together and more apart. One is in the north and the other is in the south, 400 kilometers apart. At the cocktail party, Bai Ze took the initiative to help Lin Si, who had never met before, and Lin Si gave her contact information to the emergency person in order to express her gratitude. Bai Ze hurried to catch a flight and said that Lin Si would treat him to dinner if he came to Qingcheng again in the future. The two contacted each other through mobile phones and became eager to become a couple. However, because they were about to get married and neither of them wanted to leave their city and Lin Si had serious psychological problems, they faced a choice.