Mathieu had created a plainchant with a complex rhythm. The music had swarmed over the abbot’s final defenses. Walls he didn’t realize he still had. And the notes, the neumes, the lovely voice had found the chord at Dom Philippe’s core.

And for a few moments the abbot had known complete and utter bliss. Had resonated with love. Of God, of man. Of himself. Of all people and all things.

But now all he heard was the sobbing in the stall beside him.

Frère Luc had finally made his choice. He’d left the porterie and killed the prior.

*   *   *

Gamache felt himself propelled backward and braced himself. His back connected with the stone wall and the breath was knocked out of him.

But by far the biggest shock came in that split second before impact, when he realized who was doing this.

He gasped for air and felt Jean-Guy’s hand go to his pocket. After the pills.

Gamache grabbed the hand and twisted. Beauvoir howled and fought harder, thrashing and wailing. Knocking Gamache in the face and chest. Knocking him backward again in a desperate, single-minded drive to get at what was in Gamache’s pocket.

Nothing else mattered. Beauvoir twisted and shoved and would have clawed his way through concrete to get at that pill bottle.

“Stop, Jean-Guy, stop,” Gamache shouted, but knew it was no use. Beauvoir was out of his mind. The Chief brought his forearm up and held it to Beauvoir’s throat, just as he saw something that almost stopped his heart.

Jean-Guy Beauvoir went for his gun.

*   *   *

“All those neumes,” Frère Luc slobbered, his voice wet and messy. There was a snuffle, and the abbot imagined the long black sleeve of the robe drawn across the runny nose. “I couldn’t believe it. I thought it was a joke, but the prior said it was his masterpiece. The result of a lifetime studying chants. The voices would be sung in plainchant. Together. The other neumes were for instruments. An organ and violins and flute. He’d been working on it for years, Père Abbé. And you didn’t even know.”

The young voice was accusatory. As though it was the prior who had sinned and the abbot who had failed.

Dom Philippe looked through the grillwork of the confessional, trying to glimpse the other side. To see the young man he’d followed since the seminary. Had watched, from a distance, as he’d grown and matured, and chosen holy orders. As his voice had begun the long drop, from his head to his heart.

But, unknown to the abbot or the prior, that drop had never been completed. The lovely voice had gotten stuck behind a lump in the young man’s throat.

After the success of their first recording, but before the rift, Mathieu and the abbot had met for one of their talks in the garden. And Mathieu had said the time had come. The choir needed the young man. Mathieu wanted to work with him, to help shape the extraordinary voice before some less gifted choirmaster got hold of him.

One of the elderly brothers had just died, and the abbot had agreed, with some reluctance. Frère Luc was still so young, and this was such a remote monastery.

But Mathieu had been convincing.

And now, peering through the grille at Mathieu’s killer, the abbot wondered whether it was the voice Mathieu hoped to influence, or the monk.

Did Mathieu realize that the other brothers might be reluctant to sing such a revolutionary chant? But if he could recruit the young, lonely monk to the abbey, he could get him to do it. And to not only sing the chant, but write the words.

Mathieu was magnetic, and Luc was impressionable. Or so the prior had thought.

“What happened?” the abbot asked.

There was a pause and more ragged inhales.

The abbot didn’t press anymore. He tried to tell himself it was patience that guided him. But he knew it was fear. He didn’t want to hear what came next. His rosary hung from his hands and his lips moved. And he waited.

*   *   *

Gamache grabbed at Beauvoir’s hand, trying to loosen the gun. From Jean-Guy’s throat came a wail, a cry of desperation. He fought wildly, flailing and kicking and bucking but finally Gamache twisted Beauvoir’s arm behind his back and the firearm clattered to the floor.

Both men were gasping for breath. Gamache held Jean-Guy’s face against the rough stone wall. Beauvoir bucked and sidled but Gamache held firm.

“Let go,” Beauvoir screamed into the stone. “Those pills are mine. My property.”

The Chief held him there until his twisting and bucking slowed, and stopped. And all that was left was a panting young man. Exhausted.

Gamache took the holster from Beauvoir’s belt then reached into Jean-Guy’s pocket and took his Sûreté ID. Then he stooped for the gun and turned Beauvoir around.