A modern youth time-travels to the Dayong Dynasty, becoming Su Moyuan, a concubine-born son of the Town-Guo Duke's Mansion who suffers all kinds of persecution. Near death, he awakens the causality-law enforcement system Xuanlin Record, possessing the Scale Eye ability. He escapes the Duke's Mansion, joins the Xuanlin Pavilion, cracks serial murder cases, and investigates old unsolved cases. All the way, he fights against the powerful and wealthy, parts the thick fogs of salt tax corruption and the Donglin wrongful case, holds fast to the justice in his heart in the vortex of court scheming, and embarks on the journey to uncover imperial court secrets.