They came to the overpass; the bridge was gone, collapsed in sheets of broken concrete. The highway below was a choked gulley of cars and debris, completely impassable. There was nothing to do but try to go around. Peter guided the Humvee east, tracing the highway below them. A few minutes later they came to a second bridge, which appeared intact. A gamble, but they were running out of time.

He radioed Sara. “I’m going to try to get across. Wait until we’re over.”

Their luck held; they traversed it without incident. Pausing on the far side for Sara to cross, Peter took the map from Caleb once again. If he was correct, they were on Las Vegas Boulevard South; the airport, with its fuel tanks, would be due east.

They pressed on. The landscape began to change, thickening with structures and abandoned vehicles. Most were pointed south, away from the city.

“Those are Army trucks,” said Caleb.

A minute later they saw the first battle tank. It was resting upside down in the center of the road, like a huge capsized turtle; both of its tracks had been blown off its wheels.

Alicia crouched to peek her head back into the cabin. “Pull forward,” she said. “Slowly.”

He turned the wheel to navigate around the overturned tank. By now it was obvious what lay ahead: the city’s defensive perimeter. They were moving through a vast debris field of tanks and other vehicles. Peter saw, beyond it, a line of sandbags backed against a concrete barrier, topped with coils of wire.

“What do you want to do now?” Sara asked over the radio.

“We’ll have to go around somehow.” He released the Talk button and lifted his voice to Alicia, who was scanning with the binoculars. “Lish! East or west?”

She ducked down again. “West. I think there’s a break in the wall.”

It was getting late; the attack the night before had left them all shaken. The last hands of daylight were like a funnel, drawing them down toward night. With each passing minute, the decisions they made became more irrevocable.

“Alicia says west,” Peter radioed.

“That’ll take us away from the airport.”

“I know. Put Hollis on again.” He waited for Hollis’s acknowledgment, then continued: “I think we have to use the gas we’ve got to find shelter for the night. All those buildings up ahead, there has to be something we can use. We can backtrack to the airport in the morning.”

Hollis’s voice was calm, but Peter could detect the underlying note of worry. “It’s your call.”

He glanced through the rearview at Alicia, who nodded.

“We’re going around,” Peter said.

·   ·   ·

The break in the perimeter was a ragged gap twenty meters across. The remains of a burned-out tanker truck lay on its side near the opening. Probably, Peter thought, the driver had tried to run the blockade.