Although usually associated with the 1920s and the '30s, in fact the Art Deco style had begun to emerge in France prior to the advent of the First World War. But it was during the interwar years that the style, reaching full maturity, was adopted by the international elite as the perfect expression of modern opulence and elegance, and to this day Art Deco designs are redolent of the age of Jazz, cocktails, the Charleston, speakeasies, Hollywood glamour, New York skyscrapers and, above all, style. The '20s was also a period of great technological advances in engineering and transportation, and the perpetual modernity and futuristic aura of Art Deco are evocative of this too. Here, BBC Antiques Roadshow expert Eric Knowles provides a lavishly illustrated guide to this most alluring and timeless of styles.