’Very well,’ Alondra assented, somewhat ungraciously. He was getting restive at the masterful manner of this stranger, who, after all, was only an under-official—or, as he himself had admitted, a kind of slave. ’What is your name?’ he added as an afterthought. The stranger hesitated for a brief space, then said, ’You may call me Malto.’ With that he turned away, and began stepping down from one row of seats to another, walking as if plunged deep in thought, and seemingly taking but little further notice of his companions. As for Gerald and Jack, they glanced at one another with perplexed and wondering looks. This cool, self-possessed young fellow had somehow impressed them favourably, and they were inclined to like him. But they did not in the least understand him; and, like Alondra, they were half-disposed to resent his assumption of so authoritative a manner. ’My stars!’ muttered Jack, under his breath, to Gerald, ’I fancy he thinks we are some of the hangers-on amongst Mr Monck’s suite!’ Meantime, the stranger had reached the floor of the place, and was now leading the way towards one end of it, which was closed in by some huge, massive-looking gates. There was something grand yet repellent about these gates. Upon them were carved two great heads as of some kind of giants, which frowned down upon them in forbidding ugliness. Their leader turned to a small wicket gate at one side, and, taking a key from his pocket, opened it, waited for the three to pass inside, then closed it and locked it behind him. They were then in a dark lobby. A moment later he opened another door, and they all passed through it. Here the three looked round in wondering silence. They were in what might have been either an immense underground cavern or a large enclosure roofed over. The light was dim, the air was oppressive, and there was a foul odour, which to the visitors seemed sickly and nauseating. Before them, at some little distance, there was a network of metal bars, which rose to a great height like an immense cage. It attracted their attention at once to the exclusion of all other surroundings, for it seemed to be the source of the evil smell which had assailed their nostrils. Suddenly they were startled by a terrible scream. It was followed by a cry as of some one in the extreme of fear and dread. At the same moment a face distorted by terror came into view behind the bars. It was only visible for a moment, then melted again into the gloom beyond. *CHAPTER XXIII.* *A FOUL DEN.* For a few moments the three friends stared without moving at the place where the agonised face had appeared. They were spellbound with horror of they knew not what; for though they could not see anything of what was going on in the den in front of them, they could hear strange sounds and weird noises.