On the mountainous border of China and Tibet in 1708, a detective must learn what a killer already knows: that empires rise and fall on the strength of the stories they tell.
Li Du was an imperial Chinese librarian. Now he is an exile. In 1780, three years of wandering have brought him to Dayan, the last Chinese town before the Tibetan border. He expects a quiet outpost barely conscious of its place within the empire, but Dayan is teeming with travelers, soldiers, and merchants. The crowds have been drawn by the promise of an unmatched spectacle; an eclipse of the sun, commanded by the Emperor himself.
Amid the frenzy, Li Du befriends an elderly Jesuit astronomer. Hours later, the man is murdered in the home of the local magistrate, and Li Du suspects it was no random killing. Everyone has secrets: the ambitious magistrate, the powerful consort, the bitter servant, the irreproachable secretary, the East India Company merchant, the nervous missionary, and the traveling storyteller who can’t keep his own story straight.
Beyond the sloping roofs and festival banners, Li Du can see the pass over Jade Dragon Mountain that will take him out of China forever. But he cannot ignore the murder that the town is all too eager to forget. As Li Du investigates, he begins to suspect that the murderer intends to kill again. The eclipse is coming. Li Du must solve the murder before the sun disappears. If he does not, then someone, perhaps Li Du himself, will never again see its light.