The large, elegant library in Agent Pendergast’s mansion on Riverside Drive was the last room one would expect to call crowded. And yet-D’Agosta reflected moodily-there was no other word for it this evening. Tables, chairs, and much of the floor were covered with plats and diagrams. Half a dozen easels and whiteboards had been erected, showing schematics, maps, routes of ingress and egress. The low-tech reconnaissance they had conducted of Herkmoor a few nights earlier had now been enhanced by high-tech remote surveillance, including false-color satellite images in radar and infrared wavelengths. Boxes lay shoved against one wall, overflowing with printouts, data dumps from computer probes of the Herkmoor network, and aerial photographs of the prison complex.

In the middle of the controlled chaos sat Glinn, nearly motionless in his wheelchair, speaking quietly in his usual monotone. He had begun the meeting with a crushingly detailed analysis of Herkmoor’s physical plant and security measures. D’Agosta needed no convincing there: if any prison was escape-proof, it was Herkmoor. The old-fashioned defenses like redundant guard posts and triple fencing had been bolstered by cutting-edge instrumentation, including laser-beam “lattices” at every exit, hundreds of digital videocams, and a network of passive listening devices set into the walls and ground, ready to pick up anything from digging to stealthy footsteps. Every prisoner was required to wear an ankle bracelet with an embedded GPS device, which broadcast the prisoner’s location to a central command unit. If the bracelet were cut, an alarm would immediately sound and an automatic lockdown sequence would begin.

As far as D’Agosta was concerned, Herkmoor was invincible.

From there, Glinn had segued to the next step in the escape plan. And this was where D’Agosta’s simmering unease had boiled over. Not only did the idea seem simplistic and inept, but, even worse, it turned out that he, D’Agosta-and he alone-was the man assigned to carry it out.

He glanced around the library, waiting impatiently for Glinn to finish. Wren had arrived earlier that evening with a set of architectural plans of the prison, “borrowed” from the private records section of the New York Public Library, and now he hovered around Constance Greene. With his luminous eyes and almost translucent skin, the man looked like a cave creature, paler even than Pendergast… if that were possible.

Next, D’Agosta’s gaze fell on Constance. She sat at a side table opposite Wren, a stack of books before her, listening to Glinn and taking notes. She was wearing a severe black dress with a row of tiny pearl buttons in the back, running from the base of her spine up to the nape of her neck. D’Agosta found himself wondering who had buttoned them up for her. More than once, he had caught her privately stroking one hand over the other, or gazing into the fire that crackled on the huge grate, lost in thought.

She’s probably as skeptical about all this as I am, he thought. Because as he looked around at their little foursome-Proctor, the chauffeur, was unaccountably absent-he couldn’t imagine a group less suited for such a daunting task. He had never really liked Glinn and his smooth arrogance, and he wondered if the man had finally met his match with the Herkmoor penitentiary.

There came a pause in Glinn’s drone, and he turned toward D’Agosta.

“Do you have any questions or comments so far, Lieutenant?”

“Yeah. A comment: the scheme is crazy.”

“Perhaps I should have phrased the question differently. Do you have any comments of substance to make?”

“You think I can just waltz in, make a spectacle of myself, and get out scot-free? This is Herkmoor we’re talking about. I’ll be lucky not to end up in the cell next to Pendergast.”

Glinn’s expression did not change. “As long as you stick to the script, there will be no problems and you will get off ‘scot-free.’ Everything has been planned down to the last eventuality. We know exactly how the guards and prison personnel will react to your every move.” Glinn suddenly smiled, his thin lips stretching mirthlessly. “That, you see, is Herkmoor’s fatal weakness. That and those GPS bracelets, which show the position of every inmate in the entire prison at the touch of a key… a most foolish innovation.”

“If I go in there and make a scene, won’t it put them on alert?”

“Not if you follow the script. There is some critical information which only you can get. And some prep work that only you can do.”

“Prep work?”

“I’ll get to that shortly.”

D’Agosta felt his frustration rise. “Pardon my saying so, but all your planning isn’t going to mean jack once I’m inside those walls. This is the real world, and people are unpredictable. You can’t know what they’re going to do.”

Glinn looked at him without moving. “You’ll forgive me for contradicting you, Lieutenant, but human beings are disgustingly predictable. Especially in an environment like Herkmoor, where the rules of behavior are mapped out in excruciating detail. The scheme may seem simple, even inane, to you. But that’s its power.”

“It’s just going to get me into deeper shit than I am already.”

After dropping this epithet, he glanced at Constance. But the young woman was staring into the fire with her strange eyes, not even seeming to have heard.

“We never fail,” Glinn said, remaining unnervingly calm and neutral. “That’s our guarantee. All you need to do, Lieutenant, is follow instructions.”

“I’ll tell you what we really need: a pair of eyes on the inside. You can’t tell me none of those guards can be turned-blackmailed, whatever. Christ, prison guards are one step away from being criminals themselves, at least in my experience.”

“Not these guards. Any attempt to turn one would be foolhardy.” Glinn wheeled himself over to a desk. “If I told you we had somebody on the inside, however, would it reassure you?”

“Hell, yes.”

“Would it secure your cooperation? Silence all these doubts?”

“If the source was reliable, yeah.”

“I believe you will find our source to be above reproach.” And with that, Glinn picked up a single piece of paper and handed it to D’Agosta.

D’Agosta glanced over the sheet. It contained a long column of numbers, with two corresponding times linked to each number.

“What’s this?” he asked.

“A schedule of guard patrols in the solitary unit during lockdown, from ten P.M. to six A.M. And this is just one of the many useful pieces of information that have come our way.”

D’Agosta stared in disbelief. “How the hell did you get it?”

Glinn allowed himself a smile-at least D’Agosta thought the faint thinning of the lips was a smile. “Our inside source.”

“And who might that be, if you don’t mind my asking?”

“You know him well.”

Now D’Agosta was even more surprised. “Not-?”

“Special Agent Pendergast.”

D’Agosta slumped in his chair. “How did he get this to you?”

This time a true smile broke over Glinn’s features. “Why, Lieutenant, don’t you remember? You brought it out.”

“Me?”

Glinn reached behind the desk, pulled out a plastic box. Looking inside, D’Agosta was surprised to see some of the trash he’d collected in his recon of the prison perimeter-gum wrappers and scraps of linen-now carefully dried, pressed, and mounted between sheets of archival plastic. When he looked closely at the linen scraps, he could just make out faint markings.

“There’s an old drain in Pendergast’s cell-as in most of the older cells at Herkmoor-which was never hooked into the modern sewage treatment system. It drains into a catchment basin outside the prison walls, which in turn empties into Herkmoor Creek. Pendergast writes us a message on a scrap of trash, sticks it into the drain, and washes it down with water from the sink, which ends up in the creek. Simple. We discovered it because the DEP had recently cited Herkmoor for the water-quality violation.”