and clear, ace,” Mark said. But he was troubled by a feeling that for the first time he was seeing his brother as he really was. The David he remembered as a brash, irrepressible young athlete had been transformed by the war into a haggard boy-man with the eyes of a neurosurgeon.
“David,” Mark whispered with sudden urgency, feeling his face grow hot with the prospect of confession. “I’ve got to talk to you.” He couldn’t stop himself. The words that became illegal the moment he uttered them came tumbling out in a flood. “The British are after me to work on a special project for them. They want me to spearhead it. It’s a type of weapon that hasn’t been used before—well, that’s not strictly true, it has been used before but not in this way and not with this much potential for wholesale slaughter—”
David caught hold of his arm. “Whoa! Slow down. What are you babbling about?”
Mark looked furtively around the pub. The background hum of voices seemed sufficient to cover quiet conversation. He leaned across the table. “A secret weapon, David. I’m not kidding. It’s just like the movies. It’s a goddamn nightmare.”
“A secret weapon.”
“That’s what I said. It’s something that would have little to guide it. It would kill indiscriminately. Men, women, children, animals—no distinction. They’d die by the thousands.”
“And the British want you to spearhead this project?”
“Right.”
David’s mouth split into an amazed smile. “Boy, did they ever pick the wrong guy.”
Mark nodded. “Well, they think I’m the right guy.”
“What kind of weapon is this? I don’t see how it could be much more destructive or less discriminating than a thousand-bomber air raid.”
Mark looked slowly around the pub. “It is, though. It’s not a bomb. It’s not even one of the super-bombs you’ve probably heard rumors about. It’s something … something like what wounded Dad.”
David recoiled, the cynicism instantly gone from his face. “You mean gas? Poison gas?”
Mark nodded.
“Shit, neither side has used gas yet in this war. Even the Nazis still remember the trenches from the last one. There are treaties prohibiting it, right?”
“The Geneva Protocol. But nobody cares about that. The U.S. didn’t even sign it.”
“Jesus. What kind of gas is it? Mustard?”
Mark’s laugh had an almost hysterical undertone. “David, nobody knows the horrific effects of mustard gas better than you or I. But this gas I’m talking about is a thousand times worse. A thousand times worse. You can’t see it, you don’t even have to breathe it. But brother it will kill you. It’s the equivalent of a cobra strike to the brain.”
David had gone still. “I assume you’re not supposed to be telling me any of this?”
“Absolutely not.”
“Well … I guess you’d better start at the beginning.”
Mark let his eyes wander over the thinning crowd. Of those who remained, he knew half by sight. Two were professors working on weapons programs. He kept his voice very low.
“One month ago,” he said, “a small sample of colorless liquid labeled Sarin was delivered to my lab for testing. I usually get my samples from anonymous civilians, but this was different. Sarin was delivered by a Scottish brigadier general named Duff Smith. He’s a one-armed old war horse who’s been pressuring me on and off for years to work on offensive chemical weapons. Brigadier Smith said he wanted an immediate opinion on the lethality of Sarin. As soon as I had that, I was to start trying to develop an effective mask filter against it. Only in the case of Sarin, a mask won’t do it. You need protection over your entire body.”
David looked thoughtful. “Is this a German gas? Or Allied stuff?”
“Smith wouldn’t tell me. But he did warn me to take extra precautions. Christ, was he ever right. Sarin was like nothing I’d ever seen. It kills by short-circuiting the central nervous system. According to my experiments, it exceeds the lethality of phosgene by a factor of thirty.”
David seemed unimpressed.
“Do you understand what I’m saying, David? Phosgene was the most lethal gas used in World War One. But compared to Sarin it’s like … nothing. One tenth of one milligram of Sarin—one speck the size of a grain of sand—will kill you in less than a minute. It’s invisible in lethal concentration, and it will pass through human skin. Right through your skin.”
David’s mouth was working silently. “I’ve got the picture. Go on.”
“Last week, Brigadier Smith paid me another visit. This time he asked how I would feel if he told me Sarin was a German gas, and had no counterpart in the Allied arsenal. He wanted to know what I would do to protect Allied cities. And my honest answer was nothing. To protect the inhabitants of a city from Sarin would be impossible. It’s not like a heavy-bomber raid. As bad as those are, people can come out from the shelters when they’re over. Depending on weather conditions, Sarin could lie in the streets for days, coating sidewalks, windows, grass, food, anything.”
“Okay,” David said. “What happened next?”
“Smith tells me Sarin is a German gas. Stolen from the heart of the Reich, he says. Then he tells me I’m wrong—there is something I can do to protect our cities.”
“What’s that?”
“Develop an equally lethal gas, so that Hitler won’t dare use Sarin himself.”
David nodded slowly. “If he’s telling the truth about Sarin, that sounds like the only thing to do. I don’t see the problem.”
Mark’s face fell. “You don’t? Christ, you of all people should understand.”
“Look … I don’t want to get into this pacifist thing again. I thought you’d come to terms with that. Hell, you’ve been working for the British since 1940.”
“But only in a defensive capacity, you know that.”
David expelled air from his cheeks. “To tell you the truth, I never really saw the difference. You’re either working in the war effort or you’re not.”
“There’s a big difference, David, believe me. Even in liberal Oxford, I’m an official leper.”
“Be glad you’re in Oxford. They’d beat the crap out of you at my air base.”
Mark rubbed his forehead with his palms. “Look, I understand the logic of deterrence. But there has never been a weapon like this before. Never.” He watched with relief as the two professors left the pub. “David, I’m going to tell you something that most people don’t know, and we’ve never discussed. Until one month
