Based on unrestricted access to private papers, "Grand Dukes and Diamonds" charts the history of one of the most influential and extraordinary families of our time: the Wernhers of Luton Hoo. The family's fortune was made by Sir Julius Wernher, financier, mining magnate, and one of the creators of modern South Africa. Luton Hoo, a country house in Bedfordshire, became the site of Wernher's magnificent collection and was duly inherited by Sir Harold Wernher and his wife Lady Zia, daughter of Grand Duke Michael of Russia and a direct descendant of Pushkin. At Luton Hoo the couple displayed her priceless collection of Faberge, and together they ran a racing stud at Newmarket. Three of their racehorses, Brown Jack, Meld and Charlottown, became legends in their time. Sir Harold also played a crucial role at D-Day, the story of which has its definitive telling within Raleigh Trevelyan's fascinating narrative.