Carry on Up the Khyber

Sir Sidney Ruff-Diamond (Sidney James) is Queen Victoria's Governor in the Indian province of Kalabar near the Khyber Pass. He must navigate a diplomatic operation after the Khasi of Kalabar (Kenneth Williams), a cunning warlord, plans to incite a rebellion in Kalabar using information that British soldiers allegedly wear underpants underneath their kilts. Meanwhile, Sir Sidney's wife, Lady Joanie Ruff-Diamond (Joan Sims), takes a photograph of the inspection of her husband's soldiers and shares it with the Khasi, who threatens to unleash an Afghan invasion force unless he sleeps with her before releasing the photo.