Zhan Zhao, a fourth-ranked imperial guard, embarks on a solo investigation after receiving evidence of a cold case. Along the way, he encounters the strong-willed Miss Huo Linglong and the justice-driven Bai Yutang. The three like-minded companions join forces to uncover clues, uphold justice, and capture criminals. Together, they work to expose a dangerous web of power that has infiltrated both the court and the martial world, ultimately restoring peace to the people.