Tang Seng (Nicholas Tse) went through a lot of hardships on his journey to obtain Buddhist scriptures. They arrived at Shache City. During the warm welcome ceremony, they were attacked by a tree demon, who captured all his disciples, leaving Tang Seng alone. In this town, Tang Seng met Meiyan (Charlene Choi), an ugly but lively lizard demon. Meiyan fell in love with Tang Seng at first sight. Tang Seng was moved by Meiyan's temperament, and both of them seriously violated the rules of heaven. Tang Seng discovered that Meiyan had hidden an alien (Fan Bingbing), and Meiyan became a rival in love with this beautiful alien. It turned out that Meiyan was not a demon, but also an alien. Meiyan rescued Tang Seng's disciples regardless of her safety and was willing to accept the interrogation of the heavenly court. In order to save poor Meiyan, Tang Seng actually picked up a big knife...