Description：Situ Jing (played by Zhang Nara), a princess of the previous dynasty who was raised in a boudoir, has a great hobby of disguising herself as a man and transforming herself into a young knight named Long. She fights for justice in the world of martial arts and thus makes friends with people from all walks of life. She is nicknamed "Little Crayfish"; the young emperor Zhu Yun (played by Su Youpeng) in the court is a young hero, but he has no room to show his strength because of the huge forces of the Three Feudatories outside and his uncle who is in control of everything inside. Therefore, although he is in a high position in the temple, his heart is far away in the world of martial arts. He travels incognito from time to time, on the one hand to investigate the people's sentiments, and on the other hand to feel the breath of freedom. Little Crayfish and Zhu Yun met in the world of martial arts, and at the same time, the prospective son-in-law Bai Yunfei (played by Lu Xing) also accidentally came in. The three of them can be said to have known each other through fighting. So a series of touching stories accompanied by conspiracy, family affection,