“Yes, you told me this afternoon. A suspect, maybe even a pedophile because I happen to have cared about a nine-year-old boy.”

Mary Fraser had managed to get under his skin and now the sore erupted.

“No,” she said. “I see a hypocrite. You saw the chance to retire and you took it, knowing no one would blame you. I see a man bloated with croissants and fear, desperate to hide out in this little village, beyond harm and beyond reproach while the rest of us keep fighting. And then you pass judgment on me? You’re a disgrace, monsieur.”

“That’s it—” said Beauvoir.

“Non,” said Gamache, breaking eye contact with Fraser to look at Jean-Guy. “Non,” he said, regaining his own composure.

Then he turned back to Mary Fraser.

“I didn’t come up here to discuss my choices,” he said. “But to warn you that someone killed Antoinette Lemaitre then tore her home apart last night. We think he was looking for the plans to Project Babylon.”

“That’s a big leap,” said Mary Fraser.

“Is it? We have every reason to believe Guillaume Couture designed the Supergun. Not Gerald Bull. Dr. Bull was the salesman, and Dr. Couture was the scientist. That’s why the gun was built here, because Dr. Couture knew the area. Knew the people. And knew no one would come looking for Project Babylon in a Québec forest. It was perfect. Until someone killed Gerald Bull.”

“These are all guesses,” she said.

“You seem resistant to the possibility,” said Gamache. “Why is that? We have a direct line connecting Dr. Couture to Gerald Bull—”

“—you have a grainy old photograph.”

“We have more than that,” he said, but Beauvoir noticed he stopped short of implicating Professor Rosenblatt.

The CSIS agent seemed perfectly composed. Her hands rested in her lap, but the fingers were tightly intertwined, turning the tips white.

“None of this is news to you, is it?” Gamache asked, tumbling to the truth. “You knew all along. Was that the file you were reading this afternoon? The name you were trying to hide from me? It was Guillaume Couture.”

She sat up straighter, as though bracing herself.

“You came here knowing the connection with Guillaume Couture, but you didn’t say anything,” said Gamache, his voice rising slightly. “You didn’t warn us, you didn’t warn Antoinette Lemaitre.”

She was silent.

“We could have saved her.”

“You could do nothing,” she snapped. “You’ve discovered more than I would have thought possible, but you have no idea what you’ve gotten hold of. Back off. Step away.”

“Why? So more people can die while you pursue whatever your own goals are?” he demanded. “And what are they exactly?”

“You’re right, we knew about Dr. Couture, of course we did,” said Mary Fraser. “But we all assumed Project Babylon died with Gerald Bull. There were rumors a gun had been built, but rumors are rife in the intelligence community, most put out as misdirection. We kept Couture under surveillance for a few years, but like you, he’d retired down here and grew tomatoes and roses and joined a bridge club, and faded away. The threat faded away.”

“Until the gun was found.”

“Yes. That was a surprise,” she admitted.

“Why didn’t you tell us about Guillaume Couture when you first saw the gun?” Beauvoir demanded. “Why didn’t you tell us about his role in creating Project Babylon, and the fact he lived in the area and had a niece?”

She said nothing.

“You didn’t want us to know,” said Beauvoir. “You want—”

Gamache placed a hand on Beauvoir’s arm, and he stopped talking.

Mary Fraser had not looked at Beauvoir when he spoke, but continued to keep Gamache in her sights.

“That was wise, Monsieur Gamache.”

Beauvoir was staring at Gamache, unclear why he’d stopped him.

“We’re here on official business, Monsieur Gamache. For CSIS. But there is someone you should be asking yourselves about. Michael Rosenblatt. Why is he still here?”

It was, Gamache thought, an evasion on her part. An attempt to redirect his attention. But it was also, he had to admit, a question that was making its way to the top of his list.

“Why do you think Professor Rosenblatt’s still here?” Beauvoir asked.

“I have no idea,” she said. “That’s your concern, not mine. I have one brief, and that’s to make sure no one else ever builds a weapon like the one we found in the woods. That’s all I care about.”