In the late Ming Dynasty, three sworn brothers who serve as the imperial secret police are dispatched to hunt down Wei Zhongxian, a eunuch politician who had been forced to resign from his influential post and exiled from Beijing. The brothers return successfully from their quest, only to find that their task was but the beginning of a strange conspiracy.

An imperial guard searches for the truth behind a conspiracy that framed him and his partners. The proof of his innocence lies with a wanted woman named Bei Zhai... but will she reveal what she knows? In this intense prequel to BROTHERHOOD OF BLADES, the only thing he can truly trust is his sword.