Once again, Lacoste and Beauvoir exchanged a quick glance, not lost on Gamache.

“What do you make of the CSIS agents?” Lacoste asked, her voice overly cheerful. Changing the subject.

“I think they know a great deal about a gun no one thought had been built by a man long dead,” said Gamache.

“So do I,” said Lacoste. “They’re not quite as bumbling as they appear. Do they really spend their days filing?”

“And reading,” Beauvoir said to Gamache. “I told you it was dangerous.”

“I don’t think the sports page will kill you, mon vieux.”

Their breakfasts arrived. Crêpes and sausages for Gamache and Beauvoir, and eggs Florentine for Lacoste.

A basket of warm, flaky croissants was placed on the table by Gabri, who smiled at Lacoste.

Beauvoir looked from Isabelle to the retreating apron of Gabri.

“He and I shared a very special night,” said Lacoste.

Armand slowly lowered his cutlery. “It was you. You told Gabri about the Supergun,” he whispered so that Professor Rosenblatt wouldn’t hear. “And asked him to spread it around.”

Isabelle Lacoste gave a very small shrug. “Oui.”

“You did it?” asked Beauvoir. “Why?”

“Everyone agrees the gun would be dangerous if it fell into the hands of people who wish us harm, but let’s not be blind,” she said. “It’s also dangerous in the hands of our own people. Especially if it’s a secret. But I didn’t do it for reasons of national security. Honestly, I’m not smart enough to understand all the working parts of that beast.”

Gamache doubted that. He’d always had great respect for his young protégé, and never more than now.

“You said it earlier, Jean-Guy,” she continued. “It’s almost impossible to investigate Laurent’s murder unless we can talk about the motive. The gun. Our duty is to Laurent, not CSIS. Besides, if the murderer wants the Supergun to be a secret, the best thing we can do is not comply. Get it out there. See if it rattles the killer. And, as you taught us, Monsieur Gamache, a rattled killer will make himself known.”

It was true. But what struck both men wasn’t her reasoning, but her calling Gamache “Monsieur.” It was the first time she had not called him Chief Inspector.

It was natural, healthy. It was true. But to Armand Gamache it felt like having a tattoo scraped off.

“And what else did I teach you?” he asked.

“Never use the first stall in a public washroom,” said Lacoste.

“Besides that.”

“That a murderer is dangerous,” she said. “And a rattled murderer is even more dangerous.”

Gamache got up. “That was a big boot you used, Chief Inspector. You hit CSIS where it hurts. In their secret parts. But we can at least see their reaction. You also delivered a swift kick to the killer and he’s still invisible to us.”