Andrew Haswell Green is dead, shot at the venerable age of eighty-three, when he thought life could hold no more surprises. The killing—on Park Avenue in broad daylight, on Friday the thirteenth—shook the city.

Born to a struggling farmer, Green was a self-made man without whom there would be no Central Park, no Metropolitan Museum of Art, no Museum of Natural History, no New York Public Library. But Green had a secret, a life locked within him that now, in the hour of his death, may finally break free.

A work of tremendous depth and piercing emotion, The Great Mistake is the story of a city transformed, a murder that made a private man infamous, and a portrait of a singular individual who found the world closed off to him—yet enlarged it.