This play is a traditional Cantonese play, and is one of the "Eight Major Songs" in Cantonese opera. Its plot is based on a ghost story which is very popular in China's southern provinces.
The Chinese believe people can be enlightened and that they can gain certain supernatural powers following many years of meditation and Taoist practice. This power is not limited to human beings, but can also extend to certain animals and plants. In this play, a willow tree envies the life of a mortal, so it changes into a beautiful woman and comes into the world after a thousand years' meditation. It confuses a talented young scholar and makes him absentminded. The scholar's family is stunned by his unusual behaviour, and asks a Taoist priest to seize the 'monster'. The priest is defeated by the ghost in the willow tree, and flees. The family thus has no option but to ask Su Dongpo for help. Su Dongpo is a famous poet of the Southern Song Dynasty, and is a local official in the area. He is a follower of Buddhism, and thus introduces a Buddhist master named Bian Cai to the family to help. With the help of the Jingang — four saints of Buddhist legend — Bian Cai is finally able to subdue the ghost.
The most vivid part of the play deals with the inabilities of the Taoist priest. This ancient drama was designed to poke fun at Taoism, while honouring Buddha at a time when Buddhism was on the rise in China. The play remained popular, however, simply because audiences were attracted by its plot and comedic episodes.