The Castle of Fu Manchu (1969) also known by its German title Die Folterkammer des Dr. Fu Man Chu, is the fifth and final Fu Manchu film with Christopher Lee portraying the title character. The spy/crime film was filmed on location in Spain and Istanbul and originally released in West Germany in 1969. It was directed by Jesús Franco and also stars Richard Greene as Nayland Smith and Howard Marion-Crawford as Dr. Petrie. Its other titles are Assignment Istanbul and The Torture Chamber of Fu Manchu.
In the film, set in the 1920s as all of the series, Fu Manchu plots to freeze the world's oceans with a diabolical new device. With his evil daughter, Lin Tang, his army of dacoits, and the help of the local crime organization led by Omar Pashu (whom Fu Manchu doublecrosses), Fu Manchu takes over the governor's castle in Istanbul which has a massive Opium reserve, to control the largest opium port in Anatolia, a fuel for his machine. He needs the help of an intelligent scientist with an ailing heart whom he has imprisoned so kidnaps a doctor and his wife to give him a heart transplant from one of his obedient servants. Opposing him from Britain's Interpol, is his arch-nemesis Nayland
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