In Crouching Tiger, Hidden Dragon, the legendary sword stolen by Jen Yu is Green Destiny.
Green Destiny is a celebrated jian, the traditional Chinese straight, double-edged sword. In the film’s story, the Wudang swordsman Li Mu Bai asks his friend Yu Shu Lien to deliver the weapon to their benefactor, Sir Te, in Beijing. The sword is described as roughly 400 years old and is treated as both a priceless artifact and a symbol of martial prestige.
A masked thief steals Green Destiny from Sir Te’s estate, and Shu Lien pursues the thief across rooftops. The thief is later revealed to be Yu Jiaolong, called Jen, a governor’s daughter whose remarkable fighting ability has been secretly developed under the influence of Jade Fox.
The sword becomes central to several of the film’s most memorable duels. Jen uses it against Shu Lien, while Li Mu Bai later takes it from her and throws it over a waterfall. The weapon’s name is sometimes confused with the film’s title or with invented alternatives such as Silver Phoenix, but Green Destiny is the canonical name in the movie’s plot.