Vernon and Irene Castle popularized ragtime dancing in the years just before World War I and made dancing a respectable pastime in America. The whisper thin, elegant Castles were trendsetters in many ways: they traveled with a black orchestra, had an openly lesbian manager, and were animal rights advocates decades before it became a public issue. Irene was also a fashion innovator, bobbing her hair ten years before the flapper look of the 1920s became popular. From their marriage in 1911 until 1916, the Castles were the most famous and influential dance team in the world. Their dancing schools and nightclubs were packed with society figures and white-collar workers alike. After their peak of white hot fame, Vernon enlisted in the Royal Canadian Flying Corps, served at the front lines, and was killed in a 1918 airplane crash. Irene became a movie star and appeared in more than a dozen films between 1917 and 1922. The Castles were depicted in the Fred Astaire...