Master of the medicinal valley and disciple of the Jade Emperor, Zi Xuan, was well on his way to becoming a deity when he met Bai Yao Yao. A little white snake spirit roaming the mortal realm as a human, Yao Yao had no intention of falling in love with a mortal, but sometimes, the best things in life happen when we least expect them.
Entwined by fate, Zi Xuan and Yao Yao should have had a beautiful life together, but when demon catcher, Fa Hai, finds the two together, he becomes obsessed with tearing them apart. Desperate to save the life of the mortal she loves, Yao Yao breaks a heavenly seal, inadvertently releasing chaos and destruction upon the human world. In order to save the world, Zi Xuan sacrifices himself, leaving a devastated Yao Yao to face a dismal eternity alone.
A thousand years pass before Yao Yao allows herself to walk among men once more. As she travels, she finds Zi Xuan, now reborn as Xu Xian. Though Xu Xian remembers nothing from his past life, Yao Yao remembers everything and vows that this time, things will be different.