Jim nodded.
"Besides," Stern said softly, "I imagine you'd like to spend some time with your son."
Jim blinked the tears away. "You don't know how bad."
"Believe me, Mr. Thurmond, I do."
"If you guys don't mind," Quinn said, "I'm going to hit the sack. Been up for over twenty-four hours now and I'm pretty wiped out."
Jim stood up and shook the pilot's hand.
"I just want to thank you again for saving us. If you and your partner hadn't shown up when you did-well, let's just say I thought we were done for."
"Don't sweat it. Besides, we almost killed you ourselves with the U.B.R.D."
"What the hell is that thing anyway? My head still hurts from it."
"A remarkable device," Stern breathed. "Basically, it utilizes ultrasonic sound as a weapon."
"The doc can explain it better than me," Quinn said,
"so I'll let him take over. I'm sure we'll see each other around. This building is big, but it ain't that big. See ya, Danny!"
Danny waved. His fingers and mouth were stained red from the lollipop.
"Bye, Mr. Quinn! Thank you for helping us."
After he left, Jim turned to the doctor.
"So it's a weapon?"
"Oh, yes," Stern replied, "and a very useful one at that. The technology was a safety feature, used to keep birds away from aircraft, farms, buildings, and such. They are very sensitive to sound, you see, much more so than a human or even a dog. It's really quite extraordinary.
They have a strong hearing ability. It assists them while hunting and helps them communicate with each other while in flight. Our device turns that strength into a weakness."
"You're telling me it gives them an ear ache?"
The doctor chuckled. "Not quite. It does much more than that. Ultrasonic sound creates extreme heat, and disrupts the nerves when played at a high frequency. It actually damages the living cells in a body. In the case of the birds, because of their sensitivity to sound, the mechanism's effects are greatly magnified. The stress forces them to flee. That's how it was used in commercial and military aviation. In our case, we simply cranked it up a notch, to use one of my grandson's favorite expressions. We broadcast at 1MHz, which virtually destroys a zombie bird's brain, and thus, destroys the zombie itself."
"But why?" Jim asked. "Why does it work on just the birds and not the other zombies? And I thought you said it only worked on living cells?"
"As for why it works on their brains even when the cells are dead-we can only speculate. These things, whatever they may be, seem to originate in their host's brain. It is my theory, and the theory of my associate, Dr. Maynard, who I'm sure you'll meet later, that deep within the host's brain, these entities may reactivate some of those dead cells and tissue. That's what gives them their mobility and reasoning capacity. The U.B.R.D. causes a loss of function in those reactivated cells inside a zombie bird's brain because of that sensitivity to sound, and because of the placement of their ears in relation to their brains."
Danny watched his father and the doctor talk. His eyes never left Jim.
"Going back to your first question," Stern continued, "we simply don't know. The effect is sporadic on the human zombies-it acts as a deterrent, but it doesn't incapacitate or destroy them. Probably because they don't have the same sound sensitivity that a bird's body does. It just isn't effective for a large-scale assault against any other creature."
"Seems like it would be," Jim mused. "I sure as hell felt it on that rooftop."
"We tried, of course. Both of our helicopters were outfitted with the devices. The first one flew over the city, using the U.B.R.D. in the streets below its flight path. The zombies did indeed fall back, and it even seemed to damage some of them, but not enough."
He paused.
"What happened exactly?" Jim asked.
Stern sighed. "The zombies had a rocket-propelled grenade launcher. They shot down the chopper while it was conducting the experiment. All onboard were killed. After that, Bates and Mr. Ramsey decided to limit its use to only the birds, since it proved effective on them."
Finished with his lollipop, Danny began to grow restless. He swung his legs back and forth beneath the examination table. The white paper covering it rustled.
"Who are Bates and Ramsey?" Jim asked.
The doctor arched an eyebrow. "Surely, you've heard of Darren Ramsey?"
"The billionaire developer?" Jim asked. "The one with his own board game and books and a reality series on TV?"
"That's him. He is our host. In fact, he designed this building. I'm sure you'll meet him soon."
"Wonderful," Jim drawled, his voice thick with sarcasm.
"I take it that you're not a fan?"
"Truthfully, doctor? I always thought he was a jerk. Just another rich yuppie with too much power and too much time on his hands." Jim immediately wished he hadn't said that, but he'd never been good at censoring himself when he was tired.
Stern smiled. "Well, he certainly has both. Especially now."
"So who's this Bates you mentioned?"
"Mr. Ramsey's personal assistant and bodyguard. A very good fellow to know-but a dangerous one as well. We all feel a lot safer with him in charge of security."
"This place is pretty secure? Even with all of those zombies out there?"
"According to Mr. Ramsey, it's impregnable, and I must say that I'm convinced. Those things outside have made numerous attempts to get inside, but so far they haven't succeeded. We're safe here-safer than anywhere else, at least."
"As long as we don't go outside?"
"We've no reason to. We have our own electricity and our own air. There's plenty of food and water and medical supplies. We can withstand a long siege."
"Why don't they just burn it down?"
"They've tried." The doctor snorted. "They've also attempted grenade and rocket attacks, swarming us with birds and rats, scaling the walls, landing a helicopter on the roof. We've repelled every attack. Trust me, Mr. Thurmond. You and your boy are safe here. So are your friends."
"Don and Frankie!" Jim exclaimed, slapping his forehead with his palm.
He winced-the action making his head throb again. "I'd almost forgotten about them. How are they?"
"Mr. De Santos suffered some contusions but otherwise, he's been given a clean bill of health."
"And Frankie?"
"My associate, Dr. Maynard, is examining her now. I imagine he'll start her on codeine or ibuprofen for the pain, and streptomycin or penicillin for the infection from her wounds. I'm sure your friend will come through just fine, as well."
Nurse Kelli dashed back in the room, breathless.
"You'd better come quick!"
"Maybe you didn't understand me the first time," Frankie spat, her hand wrapped around the fat doctor's throat. "I said you're not sticking me with any fucking needles!"
Dr. Maynard's eyes bulged and spittle flew from his lips.