Lan Yin has a blood feud and is extremely skilled in swordsmanship. After stealing the sect's secrets, she went down the mountain and was involved in a secret room murder case. Lan Yin pretended to be the unmarried woman of Cui Yuanzao, a judge of Dali Temple, and induced Cui to help her exonerate her. In the process of solving the case, Lan Yin , they found themselves being drawn deeper and deeper into the whirlpool of dynasty replacement, and their own family had been involved in it more than ten years ago.
In the end, they learned the truth, but were unable to stop the flow of history. Fortunately, they still had deep love for each other.