It makes no difference how many times you've done it, you never got used to entering a pitch black stairwell. Never knowing what you'd find, you had to make as little noise as possible. After getting off the elevator on the 14th floor, I entered the stairwell leading to the roof, making sure that I didn't let the metal door slam behind me. It takes about a minute for your eyes to adjust to the darkness. I used that minute to listen for the sound of someone's heavy breathing. I knew that I was one hell of a target on the way up the narrow staircase, but I had no choice. I had to keep going. On...