Near the rear of the fireplace, he found a few items that were not quite as carefully burned. There were half a dozen bits of paper, each with a few decipherable letters. Most contained too few letters to be of any use — mere fragments — but as he sat down he carefully put them to one side nevertheless. Of more interest were the remains of an old photograph: perhaps one of the pictures that had been removed from the walls. While most of it had been burned away, the bottom edge still remained. He could make out a portion of a desk, apparently the worktable that still stood in this room. A few pieces of paper were visible on it, along with some journals or periodicals, all too blurry to be readable.

Behind the desk stood three people in lab coats. Only their torsos were visible; everything higher in the camera’s field of view had been burned away. Logan put this to one side, too.

The final piece of recoverable paper appeared to be a memo. It had been typed on a manual typewriter, and was obviously many decades old. It was badly burned and faded, but — taking a seat at the worktable and peering at it very closely — Logan was just able to make out one fragment: “Project Sin.”

Project Sin. The page had been burned away along the right edge, and the second word was evidently incomplete.

Or was it?

Just at that moment, Logan froze. His instincts, which he had learned to trust without question, had suddenly gone off five-alarm, dumping adrenaline into his bloodstream. What was it?

And then it came again: what sounded like the stealthy tread of a foot, the faint creak of a floorboard. It seemed to be coming from beyond the wall — the wall opposite that from which he had entered the room.

Logan stood up quickly — too quickly. The chair he’d been sitting on fell backward, crashing to the floor.

He remained utterly motionless, listening intently. For a long moment, all was silence. And then came what he thought was the soft patter of steps, quickly receding.

Grabbing his flashlight, he ducked out of the hole in the wall and hurried down the hallway, moving as quickly as he could through the confusion of deconstructed offices, abandoned equipment, and intersecting hallways, trying to make his way over to the far side of the wing. After five minutes of fruitless searching, he stopped, breathing hard. He turned off his flashlight and listened in the dark. There was no sound, no light to betray the presence of another. The West Wing appeared utterly deserted.

Turning the flashlight back on, he began making his way — more slowly now — back to the forgotten room.

The elevator doors whispered open onto a dimly lit basement hallway. Jeremy Logan knew that — as with several other areas of the mansion — Lux’s underground complex was strictly off-limits to visitors, day researchers, and even some part-time staff. As a result, it did not need to maintain the rococo elegance of the more public spaces. The hallway in which he found himself, for example, had walls of dressed stone and a curved ceiling faintly reminiscent of the Roman catacombs. The air was pure and chill, however, with no smell of damp or niter.

He glanced at his watch: quarter after one in the afternoon.

The discovery of the forgotten room, along with its overpowering foreignness and mystery, had affected him more than he’d initially realized. He had awoken that morning with an uncharacteristic sense of listlessness, as if he did not know what to do next or where to turn. Newport, however, was possessed of a remarkably comprehensive public library, and a visit to it after breakfast — in particular, to its microfiche and DVD collections — had dispelled his feelings of doubt. If he did not know precisely what to do next, he at least had the germ of an idea.

He’d never been in the mansion’s basement during his tenure at Lux, and there were no signs indicating which way to go, so on a whim he headed left, past the base of the mansion’s central staircase, lacking in these subterranean depths its skin of polished marble. Within a hundred feet he was brought up short by a door of gleaming steel — a remarkable anachronism in this Poe-like space — with a single thick window of tinted Plexiglas, punctuated every few inches by small round holes set into an otherwise featureless surface. A sign on the door read RESEARCH LABORATORIES: AUTHORIZED PERSONNEL ONLY. Looking through the window, Logan made out a long hallway of exceptionally modern, high-tech design, lit by recessed fluorescent panels. Closed doors with airbrushed labels lined both sides of the hallway, receding into the distance. It looked like the laboratory complex of a research hospital, save the fact that it appeared to be utterly empty.

There was a keyed panel beside the door, and a card reader, but no phone or buzzer for admittance. Somehow, knocking didn’t seem appropriate. Logan knew that Lux kept its most modern labs here in the basement — not only did this sequestration preserve the antique feel of the other floors, but the building’s status as a historic structure made it a requirement. With a shrug, he turned away from the polished door and decided to try his luck in the other direction.

This yielded better results. After passing the elevator again and following the passage around a bend, he arrived at an open door with a sign that read ARCHIVES. Beyond the door, the walls and ceiling fell away, revealing a most impressive space bathed in bright yet pleasingly mellow light. Row after row of filing cabinets ran from front to back in achingly regular lines, but they were spaced far enough apart to forestall any sense of oppressiveness. At the far end, Logan could just make out another, smaller door, with what looked like a security station beside it. He stepped inside. Decorative wooden columns carved with encircling grape vines marched in serried ranks down the walls of the room. On the ceiling was an elaborate trompe l’oeil painting of Bacchus reclining in a glade, wineskin on his lap, his tresses and limbs being caressed by what appeared to be maenads.

Just inside the door, an elderly woman was seated at an official-looking table. A nameplate on one side of the desk read J. RAMANUJAN. She ran her eyes up and down Logan, lips pursing with an expression he could not decide was appraising or disapproving.

“May I be of assistance?” she asked.

“I’m here to research some of Lux’s early files,” Logan replied.

“ID, please.”

Logan rummaged through his jacket pockets and produced the card that had been provided him during his initial processing. The woman looked at it.

“This is a temporary card,” she told him. “I’m very sorry, but temporary staff are not allowed access to the archives.”

“Yes, I know,” Logan said, half apologetically. “That’s why I was given this, as well.” And he slipped out a letter on Lux stationary. It was written by Olafson, overriding Logan’s temporary status and giving him unrestricted access.

Ms. Ramanujan read the letter over, then handed it back. “How can I help you?”

Logan slid the letter back into his jacket. “I’m not sure, exactly.”

The woman frowned in confusion. “The researchers and scientists who use the archives are always looking for something specific.” Picking up a clipboard from her desk, she turned it toward him. It contained blank document requisition forms. “Before I can be of assistance, I’ll need to know the particular project or assignment you wish to research.”

“I fear the nature of my research is rather…amorphous. Unfortunately, I can’t be more specific until I actually investigate the files.”

This was clearly outside the archivist’s purview. “If you can’t give me a project title, or even a name, perhaps you can provide a time frame? A particular month, say, during which the work took place?”