Knox looked at him. “But you said you saw the cart with the canisters when you were here?”

He nodded and pointed at Rinehart. “You were with me, sir. Don’t you remember seeing it? I grabbed you when you stumbled getting out of the way.”

Rinehart thought for a few seconds and then his eyes widened. “I do remember that. There was a motorized cart hauling what looked like oxygen tanks.”

Puller turned to Pritchard. “Where would they be going with those?”

“I’m not sure.”

Knox said, “Well, it’s not here.”

They rushed from the room. Puller started walking full bore down the corridor while the others climbed into the carts and followed him. Knox stayed on foot and caught up to him.

“Where are you going?” she asked.

“I’m hoping I see something that will lead to something else.”

“But are you looking for anything in particular?”

“Yeah. Another way to disseminate the virus.”

“But what could that be if it’s not in the air ducts? That’s how you deploy an aerosolized bioweapon.”

But Puller wasn’t listening to her. He had stopped walking and was staring off.

Rinehart leapt off one of the carts and grabbed Puller’s arm.

“Do we need to evacuate, Puller? It’s the damn Pentagon. It’ll take time.”

Puller wasn’t listening to him either. He hustled over to a wall and snatched off a piece of paper that had been taped there. He read down it and then looked over at the group of men.

“You’re having a fire drill today?”

“Yes,” said Pritchard. He looked at his watch. “In about eight minutes. Why?”

“And you didn’t think to mention it!” barked Puller.

Pritchard bristled. “You said the Ebola would be carried through our air ducts. No one mentioned anything about our fire suppression system.”

“We don’t have time for a pissing contest,” snapped Knox.

Puller said, “You have sprinkler systems throughout the building?”

Pritchard pointed to the ceiling. They all looked up and saw a metal sprinkler head. “It was part of the renovation that was taking place before 9/11. Ironically, the part that got hit by the plane had been the first to be renovated. It’s the primary reason the building didn’t immediately collapse when the jet hit it. We had exponentially strengthened the structure. God was looking out for us that day, despite everything.”

“Well, let’s hope he’s on duty today too,” said Puller.

“But, Puller,” exclaimed Knox. “You can’t deploy an aerosolized weapon through a sprinkler system.”

“We just assumed that it was aerosolized because everyone said it was. Johnson said they hadn’t even started to examine the canisters that Aust found. They don’t know what’s in there. But you can carry water as well as air inside canisters. And you don’t have monitors on the sprinkler system, do you?”

Pritchard shook his head. “Water is water. It comes from a dedicated pipe for the fire suppression system.”

“So it’s separate from the drinking water?” said Puller.

“Yes. It only goes to the sprinkler system. It was designed that way so we wouldn’t have to worry about not having enough water pressure in the event of a fire.”

“Well, maybe today water isn’t just water. And water will actually cover everyone better then sending it through the air ducts,” noted Knox. She looked up at the sprinkler head. “The water will go everywhere, contaminate every surface. Get into every opening in someone’s skin or eyes or mouth. It’ll be a nightmare. And but for us being here they’d never know they were getting hit with Ebola instead of just H2O.”

Rinehart said, “But how would they tie it into the pipe? And how will they turn it on?”

“The second answer is easy,” said Puller. “And maybe the first answer too. When the fire drill starts, an alarm will go off, right?”

Pritchard nodded. “Correct. The alarm will sound.”

“And people will have to evacuate?”

“Can we hurry this up?” barked Knox, but Puller held up his hand, waiting for Pritchard’s answer.

“No. It would be too disruptive for a simple drill. Folks are supposed to report to certain areas that they would go to in preparation for evacuation. There they’ll get a rundown on what to do and where to evacuate in the event of an actual emergency.”

“Okay, but the sprinklers won’t come on?”

“No, of course not,” replied Pritchard.

Puller said, “Well, this time I think they will. The alarm goes off and the water turns on. People would just think it was some mechanical error. Or maybe an actual fire that just happened to occur. Or maybe some electrical short with the fire alarm system.”

Knox added, “And lots of them might go home, change clothes.”

“And contaminate thousands of more people, who would in turn contaminate thousands more,” said Puller. “And the Pentagon would be contaminated for years. It would be unusable. No one would want to come back in here. Have to hand it to these bastards, they did think this through.”

Rinehart said, “We have less than seven minutes, Puller!”

Puller grabbed Pritchard by the arm. “Where is the intake pipe?”

“This way! We’ll be there in three minutes.”

They jumped into the carts and sped off. People walking down the halls turned to stare after them, obviously sensing that something was amiss.

As they drove along Rinehart said anxiously, “People are starting to get nervous, Puller.”

“They can be nervous. We just have to stop them from being dead.”

“But should we evac—”

“General, for all I know they have eyes on this place. We start a mass exodus and they could accelerate what they’re planning. Unless you know of a way to sneak thousands of people out of this building.”

Rinehart shut his mouth and stared ahead, his brow sweaty and his eyes full of worry.

When Pritchard unlocked the door to the large water main room, Puller and the others began frantically searching the space. Puller found it, cleverly concealed in some metal framework built around the massive water pipe supplying the sprinkler system. The three silver canisters had been attached to the pipe such that they would feed directly into the water going to the sprinklers.

“How often do they check this area?” asked Puller.

“I’m not sure,” said Pritchard. “Probably not that often. There would be no need to more than perhaps monthly.”

“Even though there’s a fire drill today?” said Knox.

“It’s only a drill. No one expects water or the sprinklers to come on. They just want to test the alarms and make sure people follow the evac plan. The alarm control center is located in another part of the building.”

“Should we just pull the canisters off?” said Rinehart.

Puller shook his head. “It’ll take too long. And they might be booby-trapped. In fact, I’d be stunned if they weren’t.”

“What if we cancel the drill,” suggested Rinehart.