Sam is no ordinary woman; she's a demolitions expert. This job should have been easy; conduct a structural analysis on a building located in the remote Scottish swamps. But the eight-story building has a grim past. Deep in the night, scratching noises emanate from the walls, the same walls where fifteen years ago, the building's architect murdered his tenants by burying his victims alive, and then disappeared never to be seen again. Now, deep within the maze-like corridors of the building, the lingering shadow of this murderer seems to loom. As her paranoia slowly builds, Sam begins to sense hidden eyes spying on her. Soon, Sam will come to face the source of her night terrors, and will find out what's behind, lurking, ever closer, behind its walls.