An old stately inn stands in the heart of Seoul. It may be old, discolored, and weathered, but Nakwon Inn exudes old-world charms. As the typical cold uneventful winter comes to an end at the inn, guests start to arrive one by one as if each had promised to be present. Strangely and coincidentally, each one of them repeats Never Twice as they enter. The truth is, they all have a fateful reason to be there. What could have brought these individuals together? And what do they all have in common considering their long-term stay, assigned room numbers, gender, age, and hometown? The real reason for coming to Nakwon Inn unfolds.

A story that follows Nalan Yue, a man with two identities. He falls for the bold Rong Hua, a young maiden with a good heart yet their ties are deeper and more complicated due to the generation before them.

To support her father Rong Jingfeng in his efforts to help others, Rong Hua travels far and wide in search of the missing healing tool known as Chi Hua Zhu. However, the journey is treacherous. She falls into danger many times and gets rescued by Nalan Yue.

Unbeknownst to them, their families are caught in an intricate web of revenge and hate. Falling for each other at first sight, they decide to use their sincerity to convince the older generation to let go of the hatred in their hearts but a plan to once again hurt the Nalan clan is set in motion. At the same time, Nalan Yue is forced to become the successor of a demonic martial arts technique. Believing that Nalan Yue can overcome his inner demons, Rong Hua continues to stay by his side.