The movie was adapted from a novel by Gu Long, a popular martial arts novelist from Taiwan in the 70's and 80's. It was one of his series of books titled "Seven Weapons." Of the seven weapons, five were actually published (The Long-Lived Sword, The Jade Blade, The Sentimental Ring, The Peacock Feather, and The Parting (Lethal) Hook) and all five were made into movies.