Yona Sabar was born to an illiterate mother and peddler father in a mud hut in the mountains of Kurdish Iraq. Stephanie Kruger was born to a Manhattan CEO and his fashionable wife, holders of season tickets to the Metropolitan Opera. Yona, twenty-seven, had been in America for less than a year, for graduate school at Yale. He was depressed, homesick, and lonely, and was in New York for a long weekend to see friends from back home who now lived in the East Village. Stephanie, twenty-eight, was a caseworker at a foster agency in upstate New York. But her relationship with a boyfriend was on the rocks, so she drove to Manhattan for a few days to be with her parents. It was Labor Day 1966, late morning. Yona’s friends had gotten up early to see a parade, but Yona was too dejected to join them. He wandered the streets and eventually walked under an arch into a leafy refuge of curving paths in the heart of Greenwich Village. A sign said Washington Square Park. Yona wanted only to clear his head, to think.