In the remote and rugged northern frontier of the ancient Chinese Empire, newly appointed magistrate Judge Dee confronts the challenges of his harsh new post in Pei-chow. Here, he encounters three perplexing cases: the mysterious theft of exquisite jewels, the vanishing of a young woman entwined in a romantic affair, and a gruesome murder marked by the discovery of a woman’s nude, decapitated body. As Dee delves deeper, he finds that these seemingly unrelated crimes are intricately connected through clues embedded in the era's popular game, the Seven Board.