More than three decades after its television debut, American Gladiators remains a cultural phenomenon not quite like anything else that ever aired on screen. The American Gladiators Documentary, a two-part 30 for 30 ESPN film, tells the series’ entire epic tale, with director Ben Berman tracking down many of the show’s most charismatic figures, and along the way embarking on an odyssey to uncover the truth behind its improbable creation.