PLOT
The television serial was based on a legendary folk tale, involving a snake spirit and her male human lover, but was adapted in this version to include the presence of a black snake who is the snake spirit's mentor and the White Snake Spirit being trapped under the pagoda for 20 years, when in the original tale she was trapped under the tower for centuries.
As for the green snake, the white snake imprisons her for a short time before releasing her, unlike the original where she imprisoned her for three centuries. Xu Xian is also initially a good-for-nothing who, under the white snake's guidance, becomes an official.