So far, they had seen no trace of Fanning’s virals—no scat or animal carcasses, no sounds of movement from the buildings. Except for pigeons, the city seemed dead. Each of them had a semiautomatic rifle and a pistol; Amy also carried the sword. She had offered it to Alicia, but the woman had refused. “Peter’s right,” Alicia said. “I’ve got no use for it. Just do me a favor and cut the bastard’s head off.”

They approached from the west, via Forty-third to Vanderbilt; between the buildings, a view of Grand Central emerged. Compared to what was around it, the structure seemed modest in its dimensions, nestled like a heart in the bosom of the city. The streets around it were open to the sun, though an elevated roadway encircled the perimeter at balcony level, creating a zone of darkness beneath.

Amy checked her watch: twenty minutes to go. “We need to scout that door,” she said.

A risk, but Peter agreed. If they moved cautiously and kept low, maintaining an upward line of sight, they would be able to detect any virals beneath the overpass before they got too close.

Which was, Peter later realized, precisely what Fanning had intended them to do: to look up. Never mind Alicia’s warnings not to underestimate their adversary. Never mind that the street was suspiciously carpeted in vines, or that with each step forward the air thickened with the damp, septic odor of an open sewer. Never mind the faint sound of rustling, which might have been caused by rats but wasn’t. One careless moment was all it took. They crept beneath the overpass, every ounce of their attention focused on the empty ceiling.

Peter and Amy never even saw them coming.

—

Michael watched the numbers of the streets decline. A few were impassable, choked with vegetation or debris, others empty, as if forgotten by time. In some of the buildings, trees were growing; flocks of startled pigeons burst forth in their path, wheeling upward in huge, flapping clouds.

At the corner of Eighteenth and Broadway, they paused to rest. Alicia was breathing hard, her face glazed with sweat. “How much farther?” Michael asked.

She coughed and cleared her throat. “Eleven blocks.”

“I can do this on my own, you know.”

“Not a chance.”

The crutch was too unstable; they left it behind and went on, Michael supporting Alicia from one side. A rifle dangled over her shoulder. Her steps were labored, more hobble than walk. From time to time, she issued a tiny gasp he knew she was trying to hide. The minutes dripped away. They came to a small shelter of elaborate iron scrollwork, painted white with pigeon guano. The smell of the sea had grown strong.

“This is it,” she said.

From his pack, Michael removed a lantern and lit the wick. As they descended the stairs, he detected small movements along the floor. He paused and raised the lantern. Rats were scurrying everywhere, long brown ropes of them hugging the edges of the walls.

“Yuck,” he said.

They reached the bottom. Arched brick columns supported the roof above the tracks. On the tiled wall, a sign in gold lettering read ASTOR PLACE.

“Which direction?” Michael felt turned around in the dark.

“This way. South.”

He dropped onto the rail bed. Alicia handed him her rifle, and he helped her down. As they passed into the tunnel, the air became colder. Water sloshed at their feet. He counted their steps. At one hundred, the light of his lantern caught a frisson of movement: the hissing spray of water that shot from the edges of the bulkhead. He stepped forward and pressed his hand against the thick metal. Behind it lay untold tons of pressure, the weight of the sea, like an unfired cannon.

“How much time?” Alicia asked. She was leaning against the wall, scanning the tunnel with the rifle.

They had used forty-five minutes. He stripped off his pack and removed his supplies. Alicia was keeping watch on the far end of the tunnel. He twisted the wires of the blasting caps together, then clipped the end to the cable from the spool. Keeping everything dry would be a challenge; he had to prevent water from contacting the fuses. He returned the dynamite to his pack and searched the door for something to hang it on. Its surface was absolutely smooth.

“There,” Alicia said.

Beside the bulkhead, a long rusty screw jutted from the wall. Michael hung his pack on it, handed Alicia the detonator, and began to pull out the cable from the spool.

“Let’s go.”

They emerged into the Astor Place station and scrambled onto the platform. Unspooling the cable behind them, they headed for the stairs and ascended to the first landing. A particle-filled daylight filtered down from street level. Kneeling, Michael placed the plunger on the floor, split the cable with his teeth, and threaded one wire into each of the two slotted screws on the top of the box. Alicia was sitting on the step below him, goggles pushed up onto her forehead, her rifle pointed into the blackness below. Circles of sweat drenched her shirt at the throat and armpits; her jaw was tight with pain. As he tightened the wing nuts, their eyes met.