Liu Qianzhi, a disciple of Buyu Sect who exorcises demons, accidentally meets Xiaoqing, a fish demon who wants to cultivate into a dragon. In order to prevent others from discovering her identity as a fish demon, Xiaoqing lies that she is also a demon exorcist. After that, the two of them travel together and experience all kinds of hardships and dangers. During the journey, Xiaoqing's kind heart not only changes Liu Qianzhi's idea that all demons are evil, but also makes them rely on each other. In the end, the two join hands to thwart the evil dragon's conspiracy and protect the people of the world. Xiaoqing is willing to sacrifice her true dragon body in exchange for Liu Qianzhi's reincarnation.