At 3:58 p.m. on October 3, 1951, Bobby Thomson hit a home run off Ralph Branca. The ball sailed over the left field wall and into history. The Giants won the pennant. That moment—the Shot Heard Round the World—reverberated from the West Wing of the White House to the Sing Sing death house to the Polo Grounds clubhouse, where hitter and pitcher forever turned into hero and goat. It was also in that centerfield block of concrete that, after the home run, a Giant coach tucked away a Wollensak telescope. The Echoing Green places that revelation at the heart of a larger story, re-creating in extravagant detail and illuminating as never before the impact of both a moment and a long-guarded secret on the lives of Bobby Thomson and Ralph Branca.