Jack swung off the ladder and into the smaller duct. It was perhaps half the width of the vertical. He adjusted the headlamp lens to the widest beam and began to crawl.

“At the first intersection you turn left. I’ve cleared the dust and left a little directional arrow. I’ve done that at each intersection—the black arrows for the way in, red arrows for the way out—just in case something goes wrong with the Walkman.”

“What a comforting thought,” Jack said. But he appreciated Milkdud’s thoroughness.

He found the first pair of arrows—bracketing Dud’s handle—and made the turn.

“And that’s basically it, Jack. The arrows will lead you to the return that services Haffner’s office. If you need any help, you’ve got the cell phone. The thing is to move slowly and carefully, easing yourself along. Sudden moves that bang against the sides will send the noise far and wide. Most people ignore an occasional rattle or such from a register. But give them a series of noises moving along above their hung ceilings and they start making calls, asking what’s going on. So take it easy, Jack. We’ve given you plenty of time. Good hacking, man. This is Milkdud, signing off.”

Must think he’s Walter Cronkite or something, Jack thought as he turned off the Walkman and continued his crawl.

As he slid through the dark ducts, following the wavering beam of light stretching before him, he came to appreciate the coveralls. Its button-free front surface allowed him to glide along smoothly and silently.

The ducts, as Dud had warned, did indeed get smaller. But Jack kept following the arrows. He was, he freely admitted, utterly lost. He knew he was on the twenty-first floor of the Hand Building, and that his body was horizontal, but any orientation beyond that was a guess. Was he facing east or west, uptown or downtown? He had no idea.

That Dud had managed to hack this place—doing the elevator thing, and finding his way through this labyrinth of ductwork—on his own was astonishing.

That anyone could call it fun was simply beyond Jack.

And then Jack came to a left-pointing arrow and saw—literally—a light at the end of the tunnel.

Slim bands of fluorescent glow angled up through the louvers of a register at the end of a small duct. Jack heard voices filtering through from the room beyond, but couldn’t catch the words. And even if he could, hearing was not enough. He wanted to see who was in that room, wanted to know who was saying what.

And he couldn’t do that from here.

He had to get closer, and that meant moving into this last duct. This small last duct.