When their mother was murdered, Armand Gamache and Jean-Guy Beauvoir were children. A long-dead stone mason's letter describes his terror while bricking up an attic room somewhere in the village. When the room is found, the villagers decide to open it up. As the bricks are removed, Gamache, Beauvoir and the villagers discover a world of curiosities. But the head of homicide soon realizes there's more in that room than meets the eye. There are puzzles within puzzles, and hidden messages warning of mayhem and revenge. By opening that door, an old foe is let back into their world.
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