Rosenblatt shook his head. “File clerks.”

“Well?” Gamache asked.

“Highwater was the site of the first Supergun,” said Michael Rosenblatt. He watched Gamache as he spoke. “You’re not surprised.”

Gamache was quiet, waiting to see what Rosenblatt would say, or do, next.

“You went there, didn’t you?” said the scientist, once again fitting the pieces together. “You already knew. So why ask me?”

But his companion remained silent, and once again Rosenblatt put it together.

“It was a test? You wanted to find out if I’d tell you the truth. How did you even know I knew?”

“The redacted pages,” said Armand at last. “You read them but didn’t mention the plural. The censors took out everything, except one reference. Superguns. Everyone else who read those pages saw it. I couldn’t believe you didn’t too. So why wouldn’t you point it out? There was only one answer. Because you already knew, and hoped I hadn’t seen it.”

“Why wouldn’t I want you to know?”

“That’s a good question. Why didn’t you tell us this as soon as you saw the gun in the woods? Didn’t you think it might be important for us to know there’d once been another one, close by?”

Michael Rosenblatt took off his glasses and rubbed his face, then he replaced his glasses and looked at Gamache.

“I actually thought it didn’t matter, but hearing you say it like that, I can see how it might seem suspicious. Not many knew about the other part of Project Babylon,” said Michael Rosenblatt. “The two halves were called Baby Babylon and Big Babylon.”

“Two halves?” asked Gamache. “Of a whole?”

“No, better to call them two parts, but not of a whole. One led to the other. The first was Baby Babylon, the smaller of the two.”

“The one in Highwater.”

“Yes. It was conceived by Gerald Bull through his Space Research Corporation. Baby Babylon was a sort of open secret, like a lot of products in the arms market. Secret enough to be enticing, but out there enough to attract interest.”

“And it did,” said Gamache. “Didn’t it?” he asked when Rosenblatt didn’t answer.

“Of a sort. Baby Babylon was met with ridicule. It was called ‘Baby’ but it was so huge, so ungainly, unlike anything else out there, that it was dismissed as the product of a mind as unstable as the weapon. A fantasist. No credible engineer or physicist thought it could be built. And, if it was, it couldn’t possibly work. Only another unstable mind would commission it.”

“Saddam Hussein,” said Gamache.

“Yes. The fact Saddam was interested just confirmed everyone’s suspicion that the idea was crazy.”

He turned his mug of warm apple cider around in a lazy circle.

“They were wrong,” said Gamache.