The day after Patricia Rowan saved the world, a man named Elias Murphy brought a piece of her conscience home to roost.

She hardly needed another one. Her tactical contacts already served up an endless stream of death and damage, numbers far too vague to qualify as estimates. It had only been sixteen hours; even orders of magnitude were barely more than guesses. But the machines kept trying to pin it down, this many million lives, that many trillion dollars, as if quantifying the apocalypse would somehow render it harmless.

Maybe it would at that, she reflected. The scariest monsters always knew enough to disappear just before you turned on the lights.

She eyed Murphy through the translucent display in her head: a man eclipsed by data he couldn't even see. His face contained its own information, though. She recognised it instantly.

Elias Murphy hated her. To Elias Murphy, the monster was Patricia Rowan.

She didn't blame him. He'd probably lost someone in the quake. But if Murphy knew the role she'd played, he must also know what the stakes had been. No rational being would blame her for taking the necessary steps.

He probably didn't. Rationally. But his hatred rose from somewhere in the brainstem, and Rowan could not begrudge it.

"There's a loose end," he said evenly.

More than one.

"The ßehemoth meme got into Maelstrom," the gel-jockey continued. "Actually it's been in the net for some time, although it only really—impacted—through that one gel that you…"

He stopped before the accusation became explicit.

After a moment he began again. "I don't know how much they've told you about the—glitch. We used a Gaussian feed-forward algorithm to get around local minima—"

"You taught smart gels to protect data from Internet wildlife," Rowan said. "Somehow they generalized that into a preference for simple systems over complex ones. We innocently gave one of them a choice between a microbe and a biosphere and it started working for the wrong side. We pulled the plug just in time. That about right?"

"Just in time," Murphy echoed. Not for everyone, his eyes added. "But it had already spread the meme by then. It was linked into Maelstrom so it could act autonomously, of course."

Rowan translated: So it could immolate people without restraint. She was still vaguely amazed that the Consortium had ever agreed to give that kind of power to a head cheese. Granted there was no such thing as a human without bias. Granted no one was going to trust anyone else to decide what cities should burn for the greater good, even in the face of a microbe that could end the world. Still: give absolute authority to a two-kilogram slab of cultured neurons? She'd actually been impressed that all the kings and corpses had really agreed to it.

Of course, the thought that smart gels might have their own biases hadn't occurred to anyone.

"You asked to be kept informed," Murphy told her, "but it's really not a problem. It's just a junk meme now, it'll burn itself out in a week or two."

"A week or two." Rowan took a breath. "Are you aware of how much damage your junk meme's caused in the past fifteen hours?"

"I—"

"It hijacked a lifter, Dr. Murphy. It was two hours away from letting half a dozen vectors loose in the general population, in which case all this might have only been the beginning instead of—" — instead of, oh please God, the end of the matter…

"It could hijack a lifter because it had command authority. It doesn't have that any more, and the other gels never did. We're talking about a bunch of code that's useless to anything without real-world autonomy and which, barring some external impetus, will eventually extinguish anyway for lack of reinforcement. And as for all this—" Murphy's voice had acquired a sudden, insubordinate edge—"from what I hear, it wasn't the gels that pulled that particular trigger."

Well. Can't get much more explicit than that.

She decided to let it pass. "Forgive me, but I'm not entirely reassured. There's a plan for world destruction percolating through the net, and you're telling me not to worry about it?"

"That's what I'm telling you."

"Unfort—"

"Ms. Rowan, gels are like big gooey autopilots. Just because something can monitor altitude and weather and put down landing gear at the right time, that doesn't mean it's aware of any of those things. The gels aren't plotting to destroy the world, they don't even know the real world exists. They're just manipulating variables. And that's only dangerous if one of their output registers happens to be hooked up to a bomb on a fault line."

"Thank you for your assessment. Now if you were instructed to purge this meme, how would you go about it?"

He shrugged. "We can find perverted gels through simple interrogation, now that we know what to look for. We'd swap out tainted gels for fresh ones—we were scheduled to go to phase four anyway, so the next crop's already ripe."

"Good," Rowan. said. "Get started."

Murphy stared at her.

"Is there some problem?" Rowan asked.

"We could do it, all right, but it'd be a complete waste of—I mean, my God! Half the Pacific coast just dropped into the sea, surely there's more—"

"Not for you, sir. You have your assignment."

He turned away, crowded by invisible statistics.

"What kind of external impetus, Doctor?" She said to his back.

He stopped. "What?"

"You said it would extinguish barring some external impetus. What did you mean?"

"Something to pump up the replication rate. New input to reinforce the meme."

"What kind of input?"

He turned to face her. "There is none, Ms. Rowan. That's my point. You've purged the records, you've broken the correlations, and you've eliminated the vectors, right?"

Rowan nodded. "We—"

— killed our people—

"eliminated the vectors," she said.

"Well there you go."

She deliberately softened her voice. "Please carry out my instructions, Dr. Murphy. I know they seem trivial to you, but I'd rather take the precautions than the risk."

His face conveyed exactly what he thought of the precautions she'd already undertaken. He nodded and left without another word.

Rowan sighed and sagged back in her chair. A banner of text scrolled across her field of view: another four hundred botflies successfully requisitioned for the SeaTac mop-up. That made over five thousand of the little teleops between SeaTac and Hongcouver, racing to sniff out the bodies before typhus and cholera beat them to the trough.

Millions dead. Trillions in damages. Preferable to the alternative, she knew. It didn't help much.

Saving the world had come with a price tag attached.