We scrambled over to the air vent. We stacked a few cardboard boxes on top of each other so we could get our heads up near the vent to hear the conversation.

“Excuse me, Padre?” Ben asked. “My soul?”

“You are a very strong individual,” the priest continued. “The strongest man I have ever seen with my own eyes. I believe you could be very useful here.”

“Aww shucks. You’re too kind.”

“So, will you help?”

“What’s the alternative?”

“There is no alternative. You will answer to God.”

“Are you threatening me?”

“What the good Father is trying to say,” said another voice. I think it was the bald guy. “Is that if you do not cooperate with us, we will sacrifice you to the desert. Your death will ensure our survival.”

“But I think you will be of much more use to us alive,” the priest added. “Like I said, you are a very strong individual. We could use a man like you around here.”

Ben seemed to pause and weigh up his options. “Sure,” he said casually. “What the hell. The world’s gone to shit anyways. Might as well stick around for as long as possible.”

“Smart man,” the priest said. “But before we officially make you part of the group, we just need to ask you a few more questions.”

“Fire away.”

“Where is the Fortress?”

“You been eaves dropping on us in the vault?”

“Just answer the question.”

“There’s no point in answering it. You’ll never find the damn thing.”

“Why not?”

“It’s completely hidden. It’s off the grid.”

“Off the grid?”

“Look, you guys have a good thing going here. Trust me. You’re better off. The Fortress is a military camp, run by a bunch of terrified soldiers and a General who I’m starting to think is losing his goddamn mind. The place is a good three hundred miles north of here. You’ll never make it. And even if you do, you’ll never find it. Your best chance of survival is right here. You’re better off on your own.”

“I see,” the priest said, weighing up the information. “And tell me, what do you know about the black smoke?”

There was a long pause. Ben swore under his breath. “You’ve seen it? You’ve got one here?”

“Yes. A dark cloud. Black smoke. It shows up on the hottest days. When there is no wind.”

Another long pause. “Black smoke is bad news. The military is scared of it. The Special Forces guys, the army guys, the marines, all of ‘em. Scared out of their minds.”

“Why? Why are they so scared?”

“Because they don’t understand it. They don’t know how to fight it.”

“Where did it come from?”

“It was supposed to be the cure. They tried to fix this thing. They tried to destroy the virus. They just made it worse.”

“There’s got to be a way to kill it,” the bald guy said.

“If there is, I’d like to hear it,” Ben replied.

“May God have mercy on our souls,” the priest said.

“You should forget that stuff. There ain’t no mercy. Not anymore. Not out here.”

“I fear there is little left to do. We considered ourselves lucky to have survived the full brunt of the Oz virus. But now… now we have been pushed to the edge. The demons from the desert, the black smoke. It is too much.”

“They’re called nano-swarms.”

“What?”

“The black smoke. They’re rogue nano-swarms.”

“I don’t understand.”

“You don’t need to understand. The only thing you need to know is, if you see black smoke, you don’t have long. It’ll find you. Doesn’t matter if you’re hiding underground in a bank vault. That won’t keep it out. It’ll tear that vault apart. Eat it up.”

“You know how to stop it, don’t you?” the priest said. “You know how to fight it. Tell me.”

“Or what?”

“Please. I’m begging you.”

“No need to beg, old man.”

“Tell us,” the bald guy said, more forcefully.

“You can’t fight it. Not with guns.”

“Then how? What do we do?”

“If you see it; run. Get out while you still can.”