Lust, Caution (Chinese: 色，戒; pinyin: Sè, Jiè; Jyutping: Sik¹Gaai³) is a 2007 erotic period espionage romantic mystery film directed by Ang Lee, based on the 1979 novella by Eileen Chang. Lust, Caution is set in Hong Kong in 1938 and in Shanghai in 1942, when the city was occupied by the Imperial Japanese Army and ruled by the puppet government led by Wang Jingwei. The film depicts a group of Chinese university students from The University of Hong Kong who plot to assassinate a high-ranking special agent and recruiter working for the puppet government by luring him into a honey trap. The film is generally accepted to be based on the historical event of Chinese spy Zheng Pingru's failed attempt to assassinate the Japanese collaborator Ding Mocun.

With this film, Lee won the Golden Lion Award at the Venice Film Festival for the second time, the first being with Brokeback Mountain. The film adaptation and the story are loosely based on events that took place during the Japanese occupation of Shanghai. The film's sex scenes resulted in the film being rated NC-17 in the United States. The film grossed $67 million worldwide over $16 million budget, making it the highest grossing NC-17 rated film of all time.