"Ricky has a huge stake in the success of this company." She turned to face me. "Bobby heard him on the phone the other day, talking about his stock options. And sounding worried. I think Ricky sees Xymos as his last big chance to score. He's been here five years. If this doesn't work out, he'll be too senior to start over at a new company. He's got a wife and baby; he can't gamble another five years, waiting to see if the next company clicks. So he's really trying to make this happen, really driving himself. He's up all night, working, figuring. He isn't sleeping more than three or four hours. Frankly, I worry it's affecting his judgment."

"I can imagine," I said. "The pressure must be terrible."

"He's so sleep-deprived it makes him erratic," Mae said. "I'm never sure what he'll do, or how he'll respond. Sometimes I get the feeling he doesn't want to get rid of the swarms at all. Or maybe he's scared."

"Maybe," I said.

"Anyway, he's erratic. So if I were you I'd be careful," she said, "when you go after the swarms. Because that's what you're going to do, isn't it? Go after them?"

"Yes," I said. "That's what I'm going to do."

DAY 6

1:12 P.M.

They had all gathered in the lounge, with the video games and pinball machines. Nobody was playing them now. They were watching me with anxious eyes as I explained what we had to do. The plan was simple enough-the swarm itself was dictating what we had to do, although I was skipping that uncomfortable truth.

Basically, I told them we had a runaway swarm we couldn't control. And the swarm exhibited self-organizing behavior. "Whenever you have a high SO component, it means the swarm can reassemble itself after an injury or disruption. Just as it did with me. So this swarm has to be totally, physically destroyed. That means subjecting the particles to heat, cold, acid, or high magnetic fields. And from what I've seen of its behavior, I'd say our best chance to destroy it is at night when the swarm loses energy and sinks to the ground."

Ricky whined, "But we already told you, Jack, we can't find it at night-"

"That's right, you can't," I said. "Because you didn't tag it. Look, it's a big desert out there. If you want to trace it back to its hiding place, you've got to tag it with something so strong you can follow its trail wherever it goes."

"Tag it with what?"

"That's my next question," I said. "What kind of tagging agents have we got around here?" I was greeted with blank looks. "Come on, guys. This is an industrial facility. You must have something that will coat the particles and leave a trail we can follow. I'm talking about a substance that fluoresces intensely, or a pheromone with a characteristic chemical signature, or something radioactive… No?"

More blank looks. Shaking their heads.

"Well," Mae said, "of course, we have radioisotopes."

"All right, fine." Now we were getting somewhere.

"We use them to check for leaks in the system. The helicopter brings them out once a week."

"What isotopes do you have?"

"Selenium-72 and Rhenium-186. Sometimes Xenon-133 as well. I'm not sure what we've got on hand right now."

"What kind of half-lives are we talking about?" Certain isotopes lost radioactivity very rapidly, in a matter of hours or minutes. If so, they wouldn't be useful to me. "Half-life averages about a week," Mae said. "Selenium's eight days. Rhenium's four days. Xenon-133 is five days. Five and a quarter."

"Okay. Any of them should do fine for our purposes," I said. "We only need the radioactivity to last for one night, after we tag the swarm."

Mae said, "We usually put the isotopes in FDG. It's a liquid glucose base. You could spray it."

"That should be fine," I said. "Where are the isotopes now?"

Mae smiled bleakly. "In the storage unit," she said.

"Where is that?"

"Outside. Next to the parked cars."

"Okay," I said. "Then let's go out and get them."

"Oh, for Christ's sake," Ricky said, throwing up his hands. "Are you out of your mind? You nearly died out there this morning, Jack. You can't go back out."

"There isn't any choice," I said.

"Sure there is. Wait until nightfall."

"No," I said. "Because that means we can't spray them until tomorrow. And we can't trace and destroy them until tomorrow night. That means we wait thirty-six hours with an organism that is evolving fast. We can't risk it."

"Risk it? Jack, if you go out now, you'll never survive. You're fucking crazy even to consider it."

Charley Davenport had been staring at the monitor. Now he turned to the group. "No, Jack's not crazy." He grinned at me. "And I'm going with him." Charley began to hum: "Born to Be Wild."

"I'm going, too," Mae said. "I know where the isotopes are stored."

I said, "It's not really necessary, Mae, you can tell me-"

"No. I'm coming."

"We'll need to improvise a spray apparatus of some kind." David Brooks was rolling up his sleeves carefully. "Presumably, remotely controlled. That's Rosie's specialty."

"Okay, I'll come, too," Rosie Castro said, looking at David. "You're all going?" Ricky stared from one to another of us, shaking his head. "This is extremely risky," he said. "Extremely risky."

Nobody said anything. We all just stared at him.

Then Ricky said, "Charley, will you shut the fuck up?" He turned to me. "I don't think I can allow this, Jack…"

"I don't think you have a choice," I said.

"I'm in charge here."

"Not now," I said. I felt a burst of annoyance. I felt like telling him he'd screwed the pooch by allowing a swarm to evolve in the environment. But I didn't know how many critical decisions Julia had made. In the end, Ricky was obsequious to management, trying to please them like a child pleasing a parent. He did it charmingly; that was how he had moved ahead in life. That was also his greatest weakness.

But now Ricky stuck out his chin stubbornly. "You just can't do it, Jack," he said. "You guys can't go out there and survive."

"Sure we can, Ricky," Charley Davenport said. He pointed to the monitor. "Look for yourself."

The monitor showed the desert outside. The early afternoon sun was shining on scrubby cactus. One stunted juniper in the distance, dark against the sun. For a moment I didn't understand what Charley was talking about. Then I saw the sand blowing low on the ground. And I noticed the juniper was bent to one side.

"That's right, folks," Charley Davenport said. "We got a high wind out there. High wind, no swarms-remember? They have to hug the ground." He headed toward the passageway leading to the power station. "Time's a-wasting. Let's do it, guys." Everybody filed out. I was the last to leave. To my astonishment, Ricky pulled me aside, blocked the door with his body. "I'm sorry, Jack, I didn't want to embarrass you in front of the others. But I just can't let you do this."

"Would you rather have somebody else do it?" I said.

He frowned. "What do you mean?"

"You better face facts, Ricky. This is already a disaster. And if we can't get it under control right away, then we have to call for help."

"Help? What do you mean?"

"I mean, call the Pentagon. Call the Army. We have to call somebody to get these swarms under control."

"Jesus, Jack. We can't do that."

"We have no choice."

"But it would destroy the company. We'd never get funding again."

"That wouldn't bother me one bit," I said. I was feeling angry about what had happened in the desert. A chain of bad decisions, errors and fuckups extending over weeks and months. It seemed as if everyone at Xymos was doing short-term solutions, patch-and-fix, quick and dirty. No one was paying attention to the long-term consequences.

"Look," I said, "you've got a runaway swarm that's apparently lethal. You can't screw around with this anymore."