Ruan Xingheng, a restorer of ancient books, finds a damaged manuscript during an effort to rescue local historical documents. It has no title, no author, and not even a single complete page. The book fears no water. Instead, it needs rain for ink before the erased words will appear. It records a "Spring Flood in Hebei" from the end of the Xining era in the Northern Song, an event omitted from official histories: seventeen river relay stations caught fire at once, thirty thousand refugees vanished without a trace, and the only report the court received read, "The waters have subsided."
When Ruan Xingheng tries to fill in a missing character, the manuscript suddenly unfolds into a road leading to the past. He doesn't land in the imperial palace or become a member of a noble family. Instead, he wakes in a dilapidated copyist's shop beside an old course of the Yellow River, as an unknown scribe being hunted by the authorities. All he has with him is a bronze seal engraved with half a relay order and a book, Records of the Hebei River Relay Stations, whose contents change along with reality.
To return to his own time, he must follow the manuscript's surviving pages across eight hundred li of mountains and passes, and uncover the true cause of that spring flood. Was it a natural disaster, or did someone deliberately breach the levees and make a secret passage linking military garrisons to the capital disappear beneath the water? With every page he restores, another fragment of history emerges. With every character he changes, someone disappears from reality. Ruan Xingheng gradually realizes that the ancient book didn't send him into the past. It is using him to search for someone who was never written into history.
