Zhan Zhao of the Imperial City Bureau investigates a series of mysterious disappearances involving young women, but unexpectedly crosses paths with Bai Yutang, the Handsome Rat, who failed the military imperial examination. After an initial clash, the two come to respect each other and form an unlikely partnership: one is an imperial official, the other a wandering hero. From young women who vanish without a trace to a mighty river bursting its banks, from mysteriously stolen gunpowder to a hidden crisis threatening the imperial mausoleum, one strange case follows another. What appear to be unrelated mysteries gradually reveal a tightly woven conspiracy aimed at usurping the throne. As the chivalrous world of martial heroes collides with the political intrigues of the imperial court, the cat and mouse engage in escalating battles of wits and martial arts, with twists at every turn. When the masks finally come off, the truth proves far more shocking than anyone could have imagined!