Abbott Fahai and his assistant Neng Ren head towards a blizzard through a magical door. An ice harpy appears at the top of the mountains and turns the impetuous Neng Ren into an ice statue. She then reveals her past and reasons to kill all men. Unable to persuade the ice harpy to turn over a new leaf, Fahai is forced to fight her. The battle ends with Fahai capturing the ice harpy using a demon trapper, which releases Neng Ren from ice. Neng Ren is then tasked to confine the ice harpy at Lei Feng Pagoda, and the master and assistant head back to the door which disappears after closing behind them. At the Pagoda, Neng Ren transfers the ice harpy from the demon trapper into the magic circle, which holds other trapped demons in it.
On the other side of the mountain, two female snake demons (Qingqing and Susu) are playing around, enjoying their time when they spot a physician, Xu Xian, picking herbs at the foot of the mountain with his friends. Qingqing, being a playful snake, scares him, causing him to fall into the lake below. Susu, being gentler, assumes human form and kisses Xu Xian which allows Vital Essence to flow from her into his body thus saving him. Soon, Xu Xian wakes up and tells his friends about being kissed by a beautiful girl, which only makes them laugh.
After finding a victim of a bat demon, Fahai and Neng Ren leave the temple immediately to subdue the bat demon to avoid more casualties. Xu Xian comes across them and offers a boat ride to the city. Susu starts thinking about the day she kissed Xu Xian and decides to head to the city to find him. Meanwhile, while Qingqing is exploring the city, she came across Neng Ren and decided to help him subdue the bat demon by revealing its location. Neng Ren defeats the bat demon's cohorts, but is unable to subdue the bat demon king who bites him. Though he is subsequently saved by Fahai, Neng Ren starts turning into a bat demon himself the next day and decides to run away.
In the meanwhile, after a series of pranks, Xu Xian recognizes Susu and they spend the night together, which is rather unfortunate for Xu Xian because he does not know that he was making love to a snake in a human form.
Neng Ren is found by Qinqing and the two befriend each other. They realize that Neng Ren, despite becoming a bat demon, still has all his human taste for human food, and most of his human qualities. Meanwhile, Xu Xian and Susu wed. Shortly after Fahai saw that Xu Xian's medicines has mysterious substance after that, he gives Xu Xian a dagger that can kill demons. Susu is then chased by Fahai, who tells her to leave Xu Xian and sparing her. When she doesn't, Fahai and his disciples invade her and Xu Xian's cottage. Susu fights the battle in her snake form, but is stabbed by Xu Xian unaware of her true identity. Susu escapes but is gravely injured. Xu Xian, after realizing what he has done, decides to get the spirit root to heal her.
Helped by Susu's friend, a mouse, Xu Xian manages to retrieve a root kept inside the Lei Feng Pagoda that could save Susu, but is possessed by demons since the root was the thing that kept the demons in place. Fahai and the other monks capture Xu Xian and prepare to cast spells to banish the demons from his body. Susu recovers and she goes to find Xu Xian along with Qinqing. They are confronted by Fahai, who tries to explain to them that the spell should not be broken before it is complete. Susu, however, does not believe him and accuses him of trying to separate them so the two sisters start battling Fahai. Susu and Qingqin decide to flood the temple since Fahai won't let go of Xu Xian. After countless wounds Fahai lies back exhausted. As he looks around he sees Neng Ren helping to save his former colleagues, the monks of the temple who were trying to complete the spell to release Xu Xian from the demons. He looks up at the sky and questions whether he was right to have been a demon hunter all his life.
Susu releases Xu Xian from the spell after which Xu Xian does not have any memory of Susu. Susu blames this on Fahai, after which they have one last battle. Fahai manages to trap Susu in the temple of Lei Feng Pagoda. At this point, Susu repents and asks to see Xu Xian just one last time, as she could accepted any punishments as long as she could see him for the last time. Simultaneously, Fahai gets the answer to his question and understands what he must do. Filled with the divine spirit, he lifts up the pagoda to allow Susu's last wish to come true.
After a brief reunion with Xu Xian, she tells him of her story of having meditated for a thousand years before she met him. She tells him that it was all worth less than a moment with him, that even he doesn't remember her, her memory of love with him is enough, and that even if she has to die or live with pain, she won't regret how much she has to suffer to see him one last time. She kisses him, causing him to remember everything. As the pair go to kiss one last time Susu is sucked back into the temple, leaving Xu Xian chasing her as both cry and reach out for each other.
Qingqing, watching all this from a distance with Neng Ren, tells him that she doesn't want to love anyone as her sister loved Xu Xian, and leaves saying that he will never be a true bat demon anyway.
After this, we see Xu Xian picking herbs around the temple and inside Susu has returned to her true form as a white snake trapped inside the temple. Fahai is seen walking the mountainside when suddenly Neng Ren (now a complete bat demon) appears alongside him. Throwing him an apple to eat Fahai tells him that he has grown used to his new look, and they continue on the journey together again.Jet Li as Abbott Fahai (法海)
Raymond Lam as Xu Xian (许仙)
Eva Huang as White Snake/Susu (素素)
Charlene Choi as Green Snake/Qingqing (小青)
Wen Zhang as Neng Ren (能忍)
Jiang Wu as Turtle Devil (龜妖)
Vivian Hsu as Ice Harpy(雪妖)
Miriam Yeung as Rabbit Devil (兔)
Chapman To as Toad Monster/Gugu (蛤蟆怪)
Law Kar-ying as Mysterious Herbalist (神秘藥師)
Lam Suet as Chicken Devil (雞妖)
Sonija Kwok as Bu Ming (不明)
Angela Tong as Cat Devil (貓妖)
Michelle Wai as Bat Devil (蝙蝠妖女)
Leading actors Ethan Juan, Peter Ho, Mark Chao and Raymond Lam auditioned for the lead role in the film. In the end, Lam got the role. It was reported that Juan and Chao were dropped as they were deemed to be not well known enough in China and Ho's image did not suit the male lead.
Jet Li was announced to be part of the cast during early pre-production. However, his role was not revealed until September 2010, when some actors' roles were announced, including Jet Li as Fa Hai, Eva Huang as White Snake, Raymond Lam as Xu Xian, Charlene Choi as Green Snake and Wen Zhang, whom Li invited to play his disciple Neng Ren.
Regarding the action scenes, Jet Li said he had never been this exhausted before. Li said,
After fighting the White Snake, fight the Green Snake. After fighting the Green Snake, then fight the Demon. After fighting this Demon, then fight another Demon. After fighting this Demon, then fight the Water Monster. Everyday on set I was letting out a big sigh.
Raymond Lam said he was always being hit by others,
Especially Ah Sa, she even requested for the director to add fight scenes. As a result, added scenes to hit me! Furthermore she fought much more fiercely than before!
Filming wrapped on January 16, 2011. Originally titled Madame White Snake in English, the film logo was unveiled during the production wrap press conference with the new official English title, It's Love. However, the English title was changed to The Sorcerer and the White Snake when the distributor was announced. The actual title used has been The Emperor and the White Snake, both on DVD and at IMDb.