Shortly after dawn one December morning, Bob Menzer rode the freight elevator to the forty-fifth floor of the Hearst Tower, on Eighth Avenue in Manhattan, and opened the door to the roof. The weather was clear and cold; five hundred feet above the street, the rooftop was silent except for the hum of giant air-conditioning fans. Menzer, a soft-spoken, bearded fifty-four-year-old with a nervous laugh, narrow blue eyes, and a thick shock of brown hair, was the rigging foreman of the tower’s window-cleaning crew. He had risen at 3 a.m. to travel to Hearst from his home in Queens, and clocked in at five. He wore dark-blue overalls, a yellow fall-protection harness, and heavy gloves. Carrying a checklist on a clipboard, he was joined by Ron Brown, fifty-eight, and Janusz Kasparek, fifty-five. Together they prepared to go “over the side” in the basket of the most complex window-washing rig in New York. Menzer chuckled as he showed me the machine for the first time. “It’s a little monster,” he said.