The modern game of football is filled with plays and formations with names like the Counter Trey, the Wildcat, the Zone Blitz, and the Cover Two. They have become part of the sport's vernacular, and yet for many fans they remain just names, often confusing ones. To rectify that, Tim Layden has drilled deep into the core of the game to reveal how these chalkboard X's and O's really work on the field, as well as where they came from and who dreamed them up.

These playbook schemes, many of them illuminated by diagrams, bear the insignia of some of the game's great innovators, men like Vince Lombardi, Don Coryell, Tom Osborne, Bill Walsh, Tony Dungy, and Buddy Ryan. But football has also been radically altered by the ingenious work of men with more obscure names, like Tiger Ellison, Emory Bellard, and Mouse Davis.

In Blood, Sweat and Chalk, Layden takes readers into the meeting rooms - and in some cases the living rooms - where the game's most significant ideas were hatched. He goes to the coaches and to the players who inspired them, so they can tell their stories. In candid conversations with some of football's most intriguing characters, Layden provides a fascinating guide to the game, helping fans to better see the subtleties of America's favorite sport.