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King--of the Khyber Rifles: A Romance of Adventure by Talbot Mundy is a political thriller story written by Talbot Mundy was an English-born American writer of adventure fiction. Based for most of his life in the United States, he also wrote under the pseudonym of Walter Galt.

Athelstan King is a British Secret Agent stationed in India at the beginning of WWI. He is attached to the Khyber Rifles regiment as a cover, but his real job is to prevent a holy war. "To stop a holy war single-handed would be rather like stopping the wind--possibly easy enough, if one knew the way." King is ordered to work with a mysterious and powerful Eastern woman, Yasmini. Can King afford to trust her? Can he afford not to?