Based on the 16th-century Chinese novel Feng Shen Yan Yi (The Investiture of the Gods), the story tells of how King Zhou of Shang becomes a tyrant due to the wiles of Daji, a vixen spirit who is disguised as one of his concubines.
When a demon cat appears and breaks the peace of Chang'an City, causing a series of strange events, poet Bai Letian and monk Kukai join hands to investigate the death of the emperor's concubine by following the trail left by the cat.