Two snake spirits, ‘White’ (Wong) and ‘Green’ (Cheung) wish to become human and experience human emotions, especially love and sex. In a world where spirits and humans should not mix, White falls in love with a local teacher, but Green becomes deeply jealous of what the couple have, causing a rift between the two.
Meanwhile, a Buddhist monk sworn to keep humans and spirits apart is struggling with a snake of his own. He is trying to make sense of his role as a monk, and his weakness seems to be his sex drive. Obviously envious of the ghostly love triangle, he throws himself into trying to expel the snakes from the human world.