The bus driver, Ah Tai, is an oddball who moves slowly, always behind in keeping time, and even slower in sensing earthquakes compared to others. Every day, he goes to the post office to send an ordinary letter to the counter clerk, Yang Xiaoqi, without knowing who it is for. Yang Xiaoqi, in complete contrast to Ah Tai, is an impatient person who rushes through everything, except her love life, which has made no progress even though she’s nearing thirty and still single. On the eve of Valentine’s Day, Yang Xiaoqi gets approached by the attractive and sunny Mr. Liu, a teacher, and finally, her romantic feelings start to blossom. However, to her surprise, when she wakes up, Mr. Liu has vanished without a trace, and Valentine’s Day has already passed?! Ah Tai, who used to come every day to mail the letters, has also disappeared without a trace. With no memory of what happened, Yang Xiaoqi embarks on a fantastical journey to find the truth.