The Shah's Rooms were the latest sensation of frivolous¹ London, and had lasted for six months with undiminished success. The building contained a number of rooms, and entertainments to suit all classes. There was a variety theatre with three performances daily, bars without number, billiard tables, lawn-tennis courts, a sawdust football ground, a motor and bicycle track, and a large hall for wrestling and boxing. But the glory of the Shah's Rooms was The Desert, as the conception was original and excellently carried out by clever workmen and designers.  
This was a vast expanse of real sand, covering several acres, and bounded on all sides by painted scenery of tropical sky and arid³ rocks, and occasional cities, and one or two pyramids. Here and there was an oasis⁴ of palms with real grass and real trees and real water, and with spotlessly white supper tents erected⁵ for the accommodation of gay parties. Caravans⁶ of camels and horses and donkeys took bands of pleasure-seekers from oasis to oasis, or into the desert itself, to dine at one of the Bedouin encampments. For entertainment, there were mirages⁷, skilfully⁹ managed with magic-lanterns, and forays of wild Arabs. Story-tellers relating the "Arabian Nights" could be hired, singers could be obtained, dancing girls could be engaged, and eastern fortune-tellers were frequently employed to read the future by means of sand diagrams. It was all very new and very amusing, and very fantastical, so it was little wonder that the Shah's Rooms were crowded nightly. They would be deserted¹⁰ when the novelty wore off, but just now fashionable London was delighted with a sham¹¹ life in a sham East.
 
Anthony and Clarice arrived about nine o'clock, and went at once to the great dancing saloon, where a masked ball was in progress. Clarice had again assumed Ferdy's evening dress, and Ackworth was astonished to see how closely she resembled her brother, when tricked out in masculine attire¹². As Anthony knew much more of the ways and means of midnight London than was good for him, he had taken Clarice to a costumier's shop in Drury Lane, and there they had procured¹³ the necessary dominos for their adventure. That of Ackworth was merely one of black silk, plain and unpretentious, but Clarice wore a red cloak with a bunch of loose white ribbons on the breast, so that Osip might recognise her. Gazing at the dancers and dresses, the two looked vainly for the purple domino with gold stars, but such a costume was nowhere to be seen. Then Clarice reminded her companion that the meeting was to take place in the Desert, so hither they bent¹⁴ their steps, and, pending¹⁵ the arrival of Osip, they partook of a hasty supper. Both were hungry, for the hurry of getting up from the country had left them no time to eat.
 
"What am I to do when Osip comes for you?" asked Anthony.
 
"Remain here," answered Clarice, looking round. "I won't go out of sight, I promise you."
 
"If you do, I shall follow," said Ackworth, resolutely¹⁶. "I am not going to let you remain alone with a known murderer. And I have brought this!"
 
Clarice looked sideways, and saw that he was holding a heavy army revolver under the folds of his domino. "You won't require to use it," she said, hastily. "If Osip means anything by asking for this meeting with Ferdy, it is, that he wishes to escape. He will, therefore, not try to hurt me in any way."
 
"You can't trust such a scoundrel," said Ackworth, quietly, "and if you go out of sight I follow--remember that."
 
They were seated under a tent on the extreme verge¹⁷ of the Desert, and between them was a small Turkish table, upon which stood a tray heaped with Eastern food. When the coffee came it was close upon ten o'clock, and Anthony lighted a cigarette; also he offered one to Clarice, who took it, smiling.
 
"I thought you did not like me to smoke?" she said.
 
"Nor do I. But you must keep up your character of Ferdy, and he is rarely without a cigarette in his mouth. Look at the mirage⁸."
 
It was extremely pretty, for on the far horizon, out of the air seemingly, grew a delicate ethereal vision of spires¹⁸ and temples and embattled walls, all white and glorious against a blue sky, quivering with heat. But Clarice was too restless to be tempted¹⁹ with such pleasures, and walked out of the tent, while Ackworth settled with the Arab attendant. Here and there she looked in vain for the purple domino, but could see no sign. The Desert was filling rapidly, and there was much laughter and much talking. Camels paced about in a stately manner, the troupes²⁰ of Bedouins were performing their raids and displaying wonderful horsemanship, and from the near tents came the chatter²¹ of merry people, enjoying the unaccustomed food. Shortly Anthony, adjusting his mask, joined her, and they stood watching for the coming of the man who was so ardently²² wanted by the police. In a few minutes Ackworth touched Clarice's arm, and drew her attention silently to a couple of men in evening dress, and unmasked, who were walking towards an oasis some distance away. Clarice nearly betrayed herself by a feminine scream of surprise, when she beheld²³ Sir Daniel Jerce arm in arm with Barras, the lawyer.
 
"What does that mean?" she asked, in a low, astonished voice.
 
Anthony shrugged²⁴ his square shoulders. "There's nothing remarkable²⁵ about that," he said, lightly. "Jerce, I suppose, feels the need of a little excitement after his hard work, so comes here."
 
"It's not the kind of place I should expect him to visit," said Miss Baird, staring after the retreating figures; "and with Mr. Barras, too, who is the driest and most uninteresting of men. I should not have thought that he would go in for amusement of any kind."
 
"Humph! Barras, like Jerce, may have two sides to his character."
 
"The sides we don't know of, scarcely seem to be respectable," retorted the girl, who felt uneasy at the sight of the two men. "I wish you would follow them, Anthony," she added, as Jerce and his companion entered the central oasis, "and learn why they are here."
 
"I don't see what good that would do, my dear. Besides, I wish to keep an eye on you and Osip."
 
"Hush²⁶! Don't mention his name. There may be spies about. I wonder when he will come?"
 
Anthony glanced at his watch. "It wants two minutes to ten," he remarked, quickly. "We had better go to the Omar Khayyám palm."
 
"I go alone," said Clarice, hastily. "If he"--she did not mention the name--"sees me with you, he won't address me. Where is the palm you speak of?"
 
"In the central oasis," said Ackworth, pointing; "see--the golden palm on the verge. But don't disappear into the oasis, Clarice, or I'll come after you. Get that chap to converse²⁷ where I can see you from this tent. I'll smoke and have a drink, and keep an eye on you both."
 
Clarice nodded, and, leaving Anthony to re-seat himself at the Turkish table, she walked slowly towards the golden palm, which was some distance away. It was an artificial tree of gigantic height, and nearly touched the glass roof which shut in the fairy Desert. Under it she saw already waiting a man clothed in a purple domino glittering with gold stars. He stood smoking a cigar, and gazed at the mirage, now enveloped²⁸ in rosy²⁹ colours.
 
"I am here," said Clarice, touching³⁰ him on the arm.
 
The man wheeled quickly, and looked searchingly at her. "A red domino with a white favour," he said, softly. "Will you please remove your mask, Mr. Baird?"
 
Anticipating this, the girl had already loosened the strings³¹, and the next moment Osip--if it was Osip--found himself staring into the face of the individual he took to be Ferdy. As he gave a nod of satisfaction, Clarice spoke³² to him in her turn. "Will you now remove your mask?" she asked, replacing her own.
 
The man glanced round, and seeing that no one was sufficiently³³ near to examine him closely, he slipped off his mask. Clarice beheld a thin face woefully scarred, especially on the cheeks. The criss-cross mark had been entirely³⁴ obliterated³⁵, and no one, at a casual glance, would have recognised Osip as he had been. It did great credit to Mrs. Dumps' powers of observation that she had so rapidly guessed--and on the stage, too--that the acrobat³⁶ who played the chrysalis was the assassin so anxiously sought for.
 
"Are you satisfied?" asked Osip, replacing his mask.
 
"I suppose you are the man," said Clarice, trying to appear calm, but shivering a little as she thought of what her companion had done, "only I don't know you by sight, remember."
 
"Didn't Mrs. Dumps tell you last night?"
 
"Yes. But how she recognised you without the criss-cross mark I cannot say," replied Clarice, quietly.
 
"Oh, trust a woman to jump to conclusions," said Osip, coolly. "It might have been my lean figure, or the shape of my head, or my general air, that she knew me by. But I certainly congratulate Mrs. Dumps on her cleverness. But you are wrong in saying that you do not know me by sight. You saw me in the High Street of Crumel."
 
Clarice suddenly recollected³⁷ that Ferdy had noticed the man in grey, and had told Jerce about him. "It was only a passing glance," she protested. "I should never have remembered you."
 
"Ah, you are not a woman," said Osip, thoroughly³⁸ imposed upon by her disguise and manly³⁹ bearing. "But we cannot speak here; someone might overhear, and I have to be careful," he ended with a slight laugh.
 
"Ugh!" said Clarice, and shuddered⁴⁰.
 
"Why do you do that?" asked Osip, suddenly and curiously⁴¹. "Granted that I am--what I am. Are you any better, Mr. Baird?"
 
Clarice felt as though cold water was running through her veins⁴². "What do you mean?" she faltered⁴³.
 
"I think you know what I mean," retorted Osip, "but we will camp in the Desert, where there will be a wide space round us, and no one can come within ear-shot without being seen. Come."
 
He led the way towards the sandy track, beckoning⁴⁴ to a picturesquely⁴⁵ attired⁴⁶ waiter to follow. Clarice cast a look in the direction of Anthony, who was watching at his tent door, and followed. In a short space of time, the sham Arab attendant--he was a Bavarian--had spread a carpet, and had arranged pillows. He also placed a Turkish stool in the middle, and waited for orders. The scarred man reclined on one set of pillows, and signalled to Clarice that she should recline on the other, which she did. "Will you have some Turkish coffee and a narghile?" he asked; "we must be strictly⁴⁷ Eastern here, you know."
 
Clarice accepted, although she secretly doubted if she could smoke a narghile, and shortly the attendant brought them what was wanted. Then he went away, and Miss Baird found herself smoking and drinking in company with a scoundrel who had killed eight people. She shivered again, as the waiter retreated, and they were left comparatively alone. Osip noticed it.
 
"Is it the cold air, or my company?" he asked, jeeringly⁴⁸.
 
"Your company," said Clarice, tartly⁴⁹.
 
"Oh, then, like doesn't draw to like. I should think after what you have done, Mr. Baird, you would be less scrupulous⁵⁰."
 
"You dare to accuse me of murdering--"
 
"Ta! Ta! ............