He grunted with satisfaction. The feel of the hilt cheered him and gave him a glow of confidence. Whatever webs of conspiracy were drawn about him, whatever trickery and treachery ensnared him, this knife was real. The great muscles of his right arm swelled in anticipation of murderous blows. He tried the farther door, fumbling with the keys as he did so. It was not locked. Yet he remembered the black man locking it. That furtive, bent figure, then, had been no jailer seeing that the bolts were in place. He had unlocked the door, instead. There was a sinister suggestion about that unlocked door. But Conan did not hesitate. He pushed upon the grille and stepped from the dungeon into the outer darkness. As he had thought, the door did not open into another corridor. The flagged floor stretched away under his feet, and the line of cells ran away to the right and left behind him, but he could not make out the other limits of the place into which he had come. He could see neither the roof nor any other wall. The moonlight filtered into that vastness only through the grilles of the cells, and was almost lost in the darkness. Less keen eyes than his could scarcely have discerned the dim gray patches that floated before each cell door. Turning to the left, he moved swiftly and noiselessly along the line of dungeons, his bare feet making no sound on the flags. He glanced briefly into each dungeon as he passed it. They were all empty, but locked. In some he caught the glimmer of naked white bones. These pits were a relic of a grimmer age, constructed long ago when Belverus was a fortress rather than a city. But evidently their more recent use had been more extensive than the world guessed. Ahead of him, presently, he saw the dim outline of a stair sloping sharply upward, and knew it must be the stair he sought. Then he whirled suddenly, crouching in the deep shadows at its foot. Somewhere behind him something was moving--something bulky and stealthy that padded on feet which were not human feet. He was looking down the long row of cells, before each one of which lay a square of dim gray light that was little more than a patch of less dense darkness. But he saw something moving along these squares. What it was he could not tell, but it was heavy and huge, and yet it moved with more than human ease and swiftness. He glimpsed it as it moved across the squares of gray, then lost it as it merged in the expanses of shadow between. It was uncanny, in its stealthy advance, appearing and disappearing like a blur of the vision.