Lin Yan, a graduate student in history, awakens a talent for "historical empathy" and is recruited by a secret organization called the Eye of Truth to become a historical corrector. He travels through twelve dynasties, uncovering truths altered by those in power: the First Emperor burned books to unify the codes of thought; Wu Zetian's wordless stele conceals the empress's final testament; Zheng He's voyages to the Western Ocean were part of an intelligence network... Every time he corrects a piece of history, the present changes in tandem. When he discovers that the same hand is behind every correction, he faces an ultimate choice: expose the "benevolent lie" that has sustained civilization, or become its new guardian?