"Nice grouping," Jim observed. The dead guy had six holes in his chest, all within six inches of one another.

Boone and I got beers from the fridge, Jim got water, and we sat around in the living room. I was thinking.

"You guys know anything about quantum mechanics? Of course not."

They didn't say anything, so I kept thinking out loud.

"Any reaction that can go in one direction can go in the other direction."

"So?"

"Okay. First of all, here's what we know: Basco, thirty years ago, dumped some whopping transformers on the north side of Spectacle Island. Covered them with dirt and forgot about them.

"In about '68, they started to worry, because they knew there was a lot of toxic stuff in those transformers. But there was nothing they could do about it until recently-the Age of Genetic Engineering. They bought out the best and brightest such company in the Boston area and told them to invent a PCB-eating bug.

"So they did. Put together some chlorine-processing plasmids and implanted them in a particular bug called Escherichiacoli. It's a bacterium that lives in everyone's bowels, helps digest food. A good bug. A very well-understood, well-studied bug, ideal for these purposes. It's what all the genetic engineers use.

"It worked. But it just barely worked in time. An old barge came along and ripped the transformers open. So they had to release the bug quickly, before they'd had a chance to test it in the lab, to clean up that mess before yours truly noticed it. And that all worked just fine. The PCBs went away.

"That's what we know. Now, from here on out, it's just my theory. Like I said, any reaction that goes one way can be reversed. Now, somewhere along the line, when these guys were trying to design a plasmid to change covalent chlorine to ionic, they had to consider the possibility of making it go the other way. Ionic chlorine, like in seawater, to covalent, like in toxic waste."

"Oh shit," Boone said.

"Once they considered that, they'd never forget it. Because a whole industry-most of the chemical industry-is founded upon a single reaction: the Chloralkali process- turning salt water into covalent chlorine. Using a very old process that takes up a hell of a lot of electrical power. It's an industry that's been on the skids for decades. But if you could design a bug that would do the same process, with no electricity, think what a kick in the ass it would be for Basco and

Boner and all those other old, decomposing corporations. Suddenly, everything they wanted to make would be ten times cheaper. The environmental regs wouldn't matter, compared to that. It would be so fucking profitable...."

"Okay, we understand why they'd want such a bug," Jim said. "You're saying they've got it?"

"They've got it. In two senses of the word. They own it, and they're infected by it. Someone screwed up. Someone at Biotronics picked his nose at the wrong time, or forgot to scrub beneath his fingernails, or something, and that wonder bug-the one that converts salt water to toxic chlorine-got into the wrong tank."

"But how did it get into that sewer line?" Boone said.

"You're Fleshy or Laughlin. You're a crafty guy. You've learned a few things since 1956 when you openly dumped your transformers on the island. This time you're going to be subtle. When it's time to eat up those PCB-eaters on the Harbor floor, you're not going to take the bacteria out in big drums and pour them into the water in broad daylight. You're not going to go out there at all. You're going to let the primeval Boston sewer system do it for you. It's full of E. coti already. You flush the bugs down the toilet at the. place where they were made, out in Natick. You pick an evening when it's starting to rain heavily. That night the sewer overflow tunnel carries your bugs twenty miles under the city and dumps them into the Harbor through a CSO in Dorchester Bay, a CSO that happens to be right near Spectacle Island.

"In most places the bugs die for lack of PCBs to eat. But some of them find their way to your huge PCB spill.

"Your plan succeeds brilliantly. The PCBs disappear. The guy from GEE gives up on it.

"Then the covalent-chlorine level starts to rise. You're not dumping PCBs, but the levels are rising anyway. It's impossible, it doesn't make sense. But after some simple tests, one of your genetic engineers figures it out. Your tank of PCB-eaters got contaminated with a very small number of bugs that do the opposite thing. They got into the sewers along with the others. At first, they didn't do very much. The size of the colony was tiny compared with the size of the PCB-eating colony. But after a few weeks, they've multiplied. They can multiply as much as they want. They have an unlimited supply of food-all the salt in the seven seas."

I drank beer and let them ponder that one.

"And all of that salt could be converted into organic chlorine?" Boone said, sounding kind of breathy.

"Let's not worry about that right at the moment," I said., Boone and Jim laughed nervously.

"It's like not worrying about nuclear war," I suggested. "We'll get used to it."

"How does this lead to Bathtub Man?" Jim said.

"Well, you realize that you're in big trouble. The guy from GEE comes back and discovers rising PCB levels, tracing them back to your CSO. He doesn't understand the whole thing yet, but you're in serious trouble now and you can't take chances. You try to kill him.

"In the meantime, you're going on to Plan B. You knew all along that your crime might come to light one day. But you're ready for it. That's why you used the sewers in the first place. You pick out one of your employees, one who's known to be a zealous worker, a fanatic for the project, and you put some of the bugs in his food. They take up residence in his bowel. Whenever he takes a shit and flushes the toilet, he's sending more of them down to the Harbor. So if the bugs ever get traced to your company, you just say, 'Well, this employee of ours got too enthusiastic and violated the extremely rigid safety procedures we have set up. As a result he got infected, and every time he used the toilet, spread more of these bugs down toward the sea.'"

"And, in the meantime, the bugs are turning the salt in this guy's food...."

"Into toxic waste. In his stomach. He gets chloracne and right away he figures out what's going on. He's being poisoned from within. So are all the people who've eaten lobsters or fish from the contaminated zones of the Harbor. Or who were dumb enough to swallow a mouthful of seawater near the CSO, like me. They're all getting chloracne, they're all getting organic-chlorine poisoning.

"Time out," Boone said. "I'm no chemist, but I know a little. It takes energy to convert salt to organic chlorine, right?" "Yeah."

"So where do these bugs-the bad bugs-get their energy supply?"

"Just a hypothesis," I said. "All the stuff I was sampling was polycyclic. Carbon rings in various numbers and combinations. If our bugs knew how to make those rings, they could get a lot of energy that way. It takes energy to break up a six-pack of carbon, right? Which means that if you make a six-pack, you get some energy out of it. And if you use that energy to make some organic chlorine, and tack that chlorine onto the six-pack, you've just made some type of useful, but toxic, chemical. That's what I was seeing out by the CSO-all kinds of polycyclic-chlorine compounds.

"Anyway, say you're Laughlin, the guy running this sorry outfit. You didn't succeed in killing the environmentalist. He got away and he's been on the phone. The toxic information is spreading. There's no way to contain it. Your only choice is to destroy the credibility of that person. You have to put a stain on his character. And what's the worst stain a guy can have right now? Being linked to terrorism. So you blow up the guy's house and say it was a bomb factory. You put a mine on Pleshy's yacht, steal the guy's car, park it nearby and say he was trying to assassinate Big Daddy. Even if the guy survives, no one will ever believe him.