He waited while Fleming digested this information.

“I told Bull he was the weak link,” said Fleming at last. “But Bull trusted the man.”

“Dr. Bull trusted you too. Seems he did not have good instincts,” said Gamache. “As it turned out, Dr. Bull was the weak link.”

Fleming studied him. Trying, Gamache sensed, to figure out how best to fillet him. Not, perhaps, physically, but intellectually, emotionally.

Gamache didn’t take his eyes off Fleming, but he was aware of Beauvoir at the door, a look of anxiety on his face. Sensing trouble.

“Yes,” said Fleming. “Gerald Bull had a good brain, but he had a huge ego and an even bigger mouth. Too many people were finding out about Project Babylon. He was even beginning to hint that Big Babylon had been built.”

Fleming shook his head slightly. It had the disconcerting effect of looking like the movement of a cheap wooden doll.

“Baby Babylon wasn’t really a secret, was it?” said Gamache. “It wasn’t meant to be. We all knew about it.”

The strategic use of “we” caught Fleming’s attention.

“That was my idea,” he said. “Build the gun on the top of a mountain, pointing into the States. Make it a ‘secret.’” His pallid hands did the air quotes.

“So that all eyes would be on it.” Gamache nodded in appreciation. “Not on the other one. The real one. And they said Gerald Bull was the genius.”

It was said sarcastically, and Fleming flushed.

“It fooled you, didn’t it?”

Gamache lifted his hands then dropped them to the cold metal table, so like an autopsy bench.

“You don’t really know who I am, do you?” said Gamache. It was like toying with a grenade. The guard at the door clutched his assault rifle tighter and even Beauvoir backed away a little.

“No one knew about Big Babylon,” said Fleming. “No one. They thought the Highwater gun was the only one, and when it failed they thought we’d failed.”

“You proved all the critics right,” said Gamache. “Project Babylon wouldn’t work. They laughed and stopped paying attention, and you quietly went about building the real thing.”

It was, Gamache had to admit, genius. A massive act of legerdemain, and the sleight of hand had worked. They were able to hide the biggest missile launcher in history because everyone was looking in the wrong direction. Until Gerald Bull’s ego roared to life.

“Of course, the real genius was Guillaume Couture,” said Gamache.

“You know about him?” said Fleming, assessing and reassessing his visitor. “Yes. We’d make a fortune, thanks to Dr. Couture.”

“Until Gerald Bull threatened the whole thing.”

Gamache took the photograph out of his pocket. He hadn’t planned to do this. In fact, his plan was not to do this. But he knew his only hope of getting information out of Fleming was to imply he already knew it.

He smoothed the picture on the metal surface then turned it around.

Fleming’s brows rose, and again his lips curled up. In his youth this man might have been attractive, but all that was gone, eaten away not by his age but by his actions.

Gamache tapped the photo. “This was taken at the Atomium in Brussels shortly before Bull was killed.”

“That’s a guess.”

“You don’t like guesses?”

“I don’t like uncertainty.”

“Is that why you killed Gerald Bull? Because he could no longer be controlled?”

“I killed him because I was asked to do it.”

Ah, thought Gamache. One piece of information.

“You probably shouldn’t have told me that,” said Gamache. “Aren’t you worried that with the gun discovered, you might be next? I’d be worried.”

He was taking a risk, he knew. But since he was in Fleming’s head, he might as well mess around and see what happened.

He saw fear in Fleming’s face and realized that this loyal agent of death was afraid of it himself. Or perhaps not so much afraid of death as the afterlife.

“Who are you?” Fleming asked yet again.

“I think you know who I am,” said Gamache.

Now he was in uncharted territory. Beyond Fleming’s head, beyond even that cavern that had once housed his heart, and into the dark and withered soul of the creature.

He was familiar with Fleming’s biography. A churchgoing, God-fearing man, he’d feared God so much he’d fled him. Into another’s arms.

That was why he’d made the Whore of Babylon. As tribute.