It all begins on a Monday, when four people board an elevator in a Manhattan office tower. Each presses a button for their floor, but the elevator proceeds, non-stop, to the top. Once there, it stops for a few seconds, and then plummets. Right to the bottom of the shaft. It appears to be a horrific, random tragedy. But then, on Tuesday, it happens again, in a different Manhattan skyscraper. And when Wednesday brings yet another high-rise catastrophe,...