The movie Sex and Zen is a 1991 Hong Kong romantic comedy film directed by Michael Mak and stars Loletta Lee, Lawrence Ng, and Kent Cheng. The film was based on the classic Chinese erotic novel called The Carnal Prayer Mat by Li Yu, written in the 17th century.
The protagonist of the movie is a young scholar named Wei Yangsheng, who is newly married to an attractive and innocent woman, but finds himself discontented with his sex life. He wants to explore the pleasures of the flesh and gain a deeper understanding of the female anatomy, but his traditional Confucian beliefs prevent him from seeking satisfaction outside of marriage.
One day, he meets a rogue named Flying Thief, who promises to teach him the secrets of seduction and introduce him to a world of sexual experimentation. However, the Flying Thief demands that Wei first undergo a gruesome operation to enlarge his penis, which he claims is necessary to satisfy women.
Wei agrees to the surgery and sets out on a series of sexual adventures with various women, both married and unmarried. Along the way, he encounters jealous husbands and deceitful mistresses, as well as the Sack Monk, a rival philosopher who disapproves of Wei's libertine lifestyle.
Despite the risks and challenges, Wei continues to pursue his quest for knowledge and pleasure, eventually learning important lessons about love, passion, and the limits of desire. The film is known for its explicit sex scenes, surreal humor, and colorful costumes, and has become a cult classic in the genre of erotic cinema.