They were two of boxing's greatest decades - featuring two of the finest heavyweight champions of all time. Dempsey and Louis fought their way from nothing to world titles at a time when the sport was winning a mass audience. Boxing grew through the boom years of the twenties then, when depression struck in the thirties, fans saw it as a symbol of their daily struggles. So they followed ever more fiercely and big fights in both decades reflected events outside the ring. As patterns of work and entertainment changed a spectacular new champion was crowned when the coming star Jack Dempsey destroyed the ageing Jess Willard in the Slaughter of Toledo. Dempsey was the hero who went to zero and back after the famous long count fight with Gene Tunney in 1927. In 1938 Brown Bomber Joe Louis fought for all of America and annihilated Hitler's champion Max Schmeling. They were busy days in the blood spattered theatre of boxing and the cast was huge. It included characters like Slapsie Maxie Rosenbloom who had nearly 300 fights then ran a nightclub in Hollywood, Hurricane Henry Armstrong who held three world titles at once, and Luis Firpo - the Wild Bull of the Pampas who charged Dempsey clean through the ropes. Battling Siki was a titleholder from Paris who, in between fights, strolled round with his pet lion on a leash. Then there was clowning Max Baer who had a hammer in his right fist, dancing Irishman Billy Conn and Cinderella Man James Braddock. There were many more as the boxing business was developed by promoters like Tex Rickard who created the first million dollar fight. A Jewish manager Joe Jacobs enraged Germany's Nazis when he took charge of Max Schmeling's career and managers like Doc Kearns showed they had more tricks than Don King. But boxing has always been more than just a sport. The determined and dedicated individual who takes charge and fights his way through has a place deep in American culture. This is the story of how at decisive times - boxing has provided champions.