The bus driver A Tai (Liu Guanting) is a slow mover. He is slower than others in sensing the time on his watch and earthquakes. He goes to the post office every day and asks the teller Yang Xiaoqi (Li Peiyu) to send a letter to someone unknown. The teller Yang Xiaoqi is completely opposite to A Tai. He is a super impatient person who rushes to do everything, but his love life has no progress. He is nearly 30 years old and still single. On the eve of Valentine's Day, Yang Xiaoqi was approached by the sunny boy Liu (Duncan Zhou Qunda). Finally, Xiaoqi and Liu, who were just beginning to fall in love, were attracted to each other. Unexpectedly, when she woke up, there was no news from Liu, and Valentine's Day had passed?! A Tai, who came to send letters every day, never appeared again... Yang Xiaoqi, who had no memory, began a fantasy journey to find the truth...