It was Hollis who answered. “Let’s do it.”

They reversed course. Angling his eyes upward through the windshield, Peter identified the structure Alicia had indicated: a white tower, fantastically tall, rising from the lengthening shadows into sunlight. It appeared solid, though of course he couldn’t see the other side; the rear of the building might be completely peeled away, for all they knew. The structure was separated from the roadway by a masonry wall and a broad, bowl-like depression, with pipes extruding from the drifts of sand and debris that littered the bottom. Peter was worried they would have to traverse this somehow, or else leave the Humvees on the street, but then they came to a break in the wall just as Alicia called down, “Turn here.”

He was able to pull the Humvee right up to the base of the tower, parking beneath a kind of portico, wreathed with skeletal vines. Sara pulled in behind him. The front of the building was boarded up, the entrance barricaded by sandbags. Exiting the vehicle, Peter felt a sudden chill; the temperature was dropping.

Alicia had opened the rear compartment and was hurriedly passing out packs and rifles. “Just take what we’ll need for tonight,” she ordered. “Whatever we can carry. Bring as much water as you can.”

“What about the Humvees?” Sara asked.

“They’re not going anywhere on their own.” Alicia, after drawing a belt of grenades over her head, checked the load on her rifle. “Hightop, do you have a way in yet? We’re losing the light here.”

Caleb and Michael were furiously working to pry loose the covering from one of the windows. With a crack of splitting plywood it yanked loose from the frame, revealing the glass behind it, caked with grime. A single stroke from Caleb’s pry bar and the glass shattered.

“Flyers,” he exclaimed, wrinkling his nose, “what’s that stink?”

“I guess we’ll find out,” Alicia said. “Okay, everybody, let’s move.”

Peter and Alicia climbed through the window first. Hollis would bring up the rear with Amy and the others in between. Dropping inside, Peter found himself in a dark hallway, running parallel with the front of the building. To his right stood a pair of metal doors, chained shut through the handles. He stepped back to the open window.

“Caleb, pass me a hammer. The pry bar, too.”

He used the sharp end of the pry bar to shatter the chain. The door swung free, revealing a wide, open space, more region than room, remarkably undisturbed. Apart from the smell-a tart chemical scent, vaguely biological-and a heavy layer of dust that coated every surface, the impression it gave was less of ruin than abandonment, as if its inhabitants had departed days ago, not decades. At the center of the space stood a large stone structure, evidently some kind of fountain, and on a raised platform in the corner, a piano, tented with cobwebs. A long counter was positioned to the left.

Peter tilted his gaze upward to the ceiling, which was bisected by elaborately carved molding into discrete, convex panels. Each was ornately painted: winged figures with sad, dewy eyes and plump-cheeked faces, set against a sky of billowing clouds.

Caleb whispered, “Is it… some kind of church?”

Peter didn’t answer; he didn’t know. Something about the winged figures on the ceiling was disquieting, even a little ominous. He turned to see Amy standing by the cobwebbed piano, gazing upward like the rest of them.

Then Hollis was beside him. “We better get to higher ground.” He felt it, too, Peter could tell, this ghostlike presence hovering over them. “Let’s try to find the stairs.”

They advanced into the building’s interior down a second, wider hallway, lined with stores-Prada, Tutto, La Scarpa, Tesorini-the names meaningless but strangely musical. There was more damage here, windows shattered, shards of glinting glass scattered over the stone floor and crunching under the soles of their boots. Many of the stores appeared to have been ransacked-counters smashed, everything overturned-while others seemed untouched, their peculiar, useless wares-shoes no one could actually walk in, bags that were too small to carry anything-still displayed in the windows. They passed signs that said SPA LEVEL and POOL PROMENADE, with arrows pointing down other, adjacent hallways, and banks of elevators, their gleaming doors sealed, but nothing that said STAIRS.

The hallway ended in a second open area, as large as the first, receding into darkness. There was something subterranean about it, as if they had stumbled upon the entrance to an immense cave. The smell was stronger here. They broke their light sticks and moved forward, sweeping the area with their rifles. The room appeared to be filled with long banks of machines, like nothing Peter had ever seen before, with video screens and various buttons and levers and switches. Before each was a stool, presumably where the machines’ operators had sat, performing their unknown function.

Then they saw the slims.

First one and then another and then more and more, their frozen figures resolving out of the gloom. Most were seated around a series of tall tables, their postures grimly comical, as if they’d been overcome in the midst of some desperate, private act.

“What the hell is this place?”

Peter approached the nearest table. Three seated figures occupied it; a fourth lay on the floor beside his overturned stool. Holding up his light stick, Peter bent to the closest body, a woman. She had toppled face-first; her head was turned to the side, her cheekbone resting on the table’s surface. Her hair, bleached of all color, formed a snarl of parched fibers around the knob of her skull. Where her teeth should have been were a pair of dentures, their plastic gums still retaining an incongruously lifelike pinkness. Ropes of golden metal wreathed her neck; the bones of her fingers, where they rested on the tabletop-she seemed to have reached out to stop her fall-were bedecked with rings, fat shining stones of every color. On the table before her was a pair of playing cards, face-up. A six and a jack. It was the same with the others, he saw: each player had two cards showing. There were more cards strewn over the table. Some kind of game, like go-to. In the center lay a heaping mound of more jewelry, rings and watches and bracelets, as well as a pistol and a handful of shells.

“We better keep moving,” Alicia said, coming up beside him.

Something was here, he thought, something he was meant to find.

“It’ll be dark soon, Peter. We have to find those stairs.”

He pulled his gaze away, nodding.

They emerged into an atrium, domed in glass. The sky above was cooling, night falling. Escalators led down to another dark recess; to the right they saw a bank of elevators, and yet another hallway, and more shops.

“Are we going in circles?” This was Michael. “I swear we came right though here.”

Alicia’s face was grave. “Peter-”

“I know, I know.” The moment of decision was upon them: keep looking for the stairs or seek shelter on the ground floor. He turned to face the group, which seemed, suddenly, too small.

“Damnit, not now.”

Mausami pointed toward the windows of the closest shop. “There she is.”

DESERT GIFT EMPORIUM, the sign read. Peter opened the door and moved inside. Amy was facing a wall of shelves by the counter, bearing a display of spherical glass objects. Amy had taken one in her hand. She gave it a hard shake, filling its interior with a flurry of movement.

“Amy, what is that?”

The girl turned, her face bright-I have found something, her eyes seemed to say, something wonderful-and held it out for him to take. An unexpected weight filled his hand: the sphere was full of liquid. Suspended in this fluid, bits of glittering white matter, like flakes of snow, were settling down upon a landscape of tiny buildings. Rising at the center of this miniaturized city was a white tower-the same tower, Peter realized, in which they now stood.