“I’m not privy to the latest developments,” Marcus said. “There is a lot of chaos.”

“I can imagine,” Jack said.

“Are you FBI?” Laurie asked.

“I am,” Marcus said.

“What does CIRG stand for?” Laurie asked.

“Critical Incident Response Group,” Marcus said. “We’re specially trained to handle NBC incidents.”

Laurie looked at Jack. She hated acronyms, especially when the definition of one led to yet another.

“That’s nuclear, biological, and chemical,” Jack explained.

Laurie nodded.

They crossed a mostly deserted Brighton Beach Avenue and passed under the el, which was part of the New York City subway system. A spiderweb of yellow caution tape blocked one of the entrances. Jack suspected that the transit system had been shut down.

After another block they came to the waterfront. Setting on the beach and boardwalk were a number of helicopters with various markings. Marcus headed for one of the smaller ones. It was an FBI Bell Jet Ranger.

He opened the door and motioned for Jack and Laurie to climb into the back. The pilot was already starting the rotors. Marcus made sure the doctors donned headsets to permit conversation.

After they’d gotten airborne, the trip to Manhattan was shockingly short, particularly for Jack, who was aware how long it had taken him on his bike the day before. The pilot landed on the green in front of City Hall. The makeshift helipad was cordoned off by firemen in hazmat suits. As the aircraft descended, the chaos that Marcus had mentioned was painfully apparent to both Jack and Laurie. In contrast to the deserted calm of Brighton Beach, there were crowds of panicky people streaming west, heading into the wind. Parked along Broadway were a number of National Guard trucks. The soldiers in protective gear had disembarked, but they were aimlessly milling about with their rifles in their hands, apparently unsure of their role.

“When the initial announcement was made, there was mass panic,” Marcus explained. “The police thought they’d be able to control it, but they couldn’t.”

Jack shook his head. Pandemonium was only going to make the situation that much worse, with contaminated people mixing with those initially uncontaminated.

Marcus didn’t wait for the rotors to stop. He opened the door and motioned for Jack and Laurie to disembark. He set off at the same rapid pace that had left Laurie behind in Brighton Beach. Jack and Laurie ran to catch up.

The construction trailer that was serving as the field command post had been placed in the plaza in front of City Hall, about six city blocks directly south of the Jacob Javits Federal Building. In that location it was safe from contamination since the day’s moderate wind was blowing from the southwest, vectoring to the northeast.