As the old man stood there he saw something coming across the moor, something which terrified him so that he lost his wits…There was the long, gloomy tunnel down which he fled. And from what? A sheep-dog of the moor? Or a spectral hound, black, silent, and monstrous? Was there a human agency in the matter? Did the pale, watchful Barrymore know more than he cared to say? It was all dim and vague, but always there is the dark shadow of crime behind it.