"HELLO AGAIN EVERYONE, I'm Howard Cosell. We're delighted to be able to bring you this very, very quaint, unique event." On Thursday night, Sept. 20, 1973, 50 million Americans, fatigued by Vietnam and Watergate, tuned in to see whether a woman could defeat a man on a tennis court. Dubbed "The Battle of the Sexes," the match pitted Billie Jean King, the 29-year-old champion of that summer's Wimbledon and a crusader for the women's liberation movement, against Bobby Riggs, the 55-year-old gambler, hustler and long-ago tennis champ who had willingly become America's bespectacled caricature of male chauvinism. Before 30,472 at...