One evening late in his life, veteran sportswriter Mike Sullivan was asked by his son what he remembered best from his three decades in the press box. The answer came as a surprise. "I was at Secretariat's Derby, in '73. That was ... just beauty, you know?" John Jeremiah Sullivan didn't know, not really - but he spent two years finding out, journeying from prehistoric caves to the Kentucky Derby in pursuit of what Edwin Muir called "our long-lost archaic companionship" with the horse. The result - winner of a National Magazine Award and named a Book of the Year by The Economist magazine - is an unprecedented look at Equus caballus, incorporating elements of memoir, reportage, and the picture gallery.