And then the shock came.

Isaac's companion, who had been leaning over the banisters, waiting for him, had loosened the muffler about his neck and opened his overcoat.

His features were now recognizable--a pale face with deep-set eyes and prominent forehead, a narrow chin, and a mouth which seemed set in a perpetual snarl.

Arnold stood gazing up at him in rapt amazement.

He had seen that face but once before, yet there was no possibility of any mistake.