With the countdown to demolition in the old city, the 30-year-old bookstore is in danger. Shop owner Lu Li unexpectedly discovered that the folder pages of an old book could connect to the time and space of the previous owner! Yellowing letters and old photos turned him into a "messenger of time", traveling through hundreds of years to make up for regrets and untie the knots of countless strangers. However, when the demolition team pressed closer, the gap between his mother and him was like a huge stone weighing on his heart. The last "time letter" from his mother's youth suddenly appeared. Lu Li was shocked to realize that what he wanted to save was not only the old street, but also his own broken family relationship. Can he find the lost love and memory on the ruins and protect the soul of the old street?
