Najia

In the autumn of 1925, at an antiques shop called Guanfu Studio in Liulichang, Beijing, twenty-four-year-old Yi Jiasheng receives an unsigned letter. On the back of the envelope is a single hexagram: Water over Lake, Oppression. The sender is his uncle-master Jin Suanpan, a former junior official in the Imperial Astronomical Bureau of the late Qing and a master of the Book of Changes, who has been missing for three years.

The letter contains just one sentence: "The great man does not lose his place, yet his words are not believed. Come at once."

Yi Jiasheng rushes to Tianjin, but Jin Suanpan has vanished without a trace. The empty house has an entire wall covered in hexagrams: the sequence of "yin waning and yang waxing" from the twelve monthly hexagrams, each stroke and blot recording the secret expansion of some force. Beneath the bedboards, he finds a manuscript. On the last page, a line of hurried cursive reads: "On the Gengzi day, the wife-and-wealth line stirs in the Dui palace. Trapped in a metal carriage, entering a secluded valley, unseen for three years. I have made more than ten calculations, and every result is the same: The proud dragon will have cause to repent."