This is a story about missing out. The two life trajectories extended separately after a brief intersection, but were repeatedly questioned by an unspoken answer over the long years. The novel takes "missing out" as its core, describing the unique slowness of that era - slow trains, slow letters, and farewells that are so slow that people have no time to save them. When Chen Mo decided to look for the girl from back then, he embarked on not only a journey of searching for her, but also a review and reconstruction of his youthful memories in the late 1990s.