During the Yongchang era of the fictional Liang dynasty, social customs are open-minded, and women may enter government service. Beneath the capital, Bianjing, lie the entangled worlds of martial factions and court politics.
A legend tells of twelve linked bizarre cases. At every crime scene, a silver needle embroidered with a zodiac sign is left behind. The first rat-head needle appeared fifteen years ago at the massacre of the Su family.
Constable Su Muyu investigates the true culprit behind her family's slaughter and discovers that the needle cases are tied to a secret of the imperial family. The true identity of the serial killer known as "Soul Embroiderer" has the power to sway every faction.
