Lin Wan, who runs an old photo studio in an old alley of "Fog City" that is about to be "off the street", has a secret that she has hidden for three years - in the old photos she develops, images that do not belong to the photos themselves will occasionally appear: sometimes it is a rickshaw from the Republic of China, sometimes it is an enamel cup from the 1980s. Until one day, a man named Lu Shiyan came to restore a yellowed family photo. The old house in the photo was exactly the same as the "Old Time House" that Lin Wan had repeatedly dreamed about. What's even more bizarre is that the old pocket watch Lu Shiyan carries with him will emit a faint light every time he is close to the old camera in the photo studio, and those "abnormal images" will become clear. As the contact deepens, Lin Wan discovers that he is a "time memoryr" who can awaken others' forgotten memories through old objects, while Lu Shiyan is the guardian who searches for "memory fragments" across time gaps. These fragments are not only related to his missing sister, but also hide the secret of the disappearing old alleys of Wucheng. While helping old neighbors retrieve their precious memories, the two of them fight against the "Forgotten Organization" that wants to use memory fragments to control others. In the process of traveling between the past and the present, they gradually piece together the time bonds that belong to them.
