"Really," said Desmond, "that rather complicates things for her, doesn't it?"

"It was in the shape of a letter of introduction, in French, without date or address, warmly recommending the dancer to our friend, Bellward."

"Who is this letter from?"

"It is simply signed 'P.', but you shall see it for yourself when you get the other doc.u.ments in the case."

"But surely, sir, such a letter might be presented in perfectly good faith..."

"It might, but not this one. This letter, as an expert has ascertained beyond all doubt, is written on German manufactured note-paper of a very superior quality;, the writing is stiff and angular and not French: and lastly, the French in which it is phrased, while correct, is unusually pompous and elaborate."

"Then..."

"The letter was, in all probability, written by a German!"

There was a moment's silence. Desmond was thinking despairingly of the seeming hopelessness of untangling this intricate webwork of tangled threads.

"And this murder, sir," he began.

The Chief shrugged his shoulders.

"The motive, Okewood, I am searching for the motive. I can see none except the highly improbable one of Miss Mackwayte being my confidential secretary. In that case why murder the father, a harmless old man who didn't even know that his daughter is in my service, why kill him, I ask you, and spare the girl? On the other hand, I believe the man Barney's story, and can see that Marigold does, too. When I first heard the news of the murder over the telephone this morning, I had a kind of intuition that we should discover in it a thread leading back to this mesh of espionage. Is it merely a coincidence that a hair, resembling Nur-el-Din's, is found adhering to the straps with which Barbara Mackwayte was bound? I can't think so... and yet..."

"But do you believe then, that Nur-el-Din murdered-old Mackwayte?

My dear Chief, the idea is preposterous..."

The Chief rose from his chair with a sigh.

"Nothing is preposterous in our work, Okewood," he replied. "But it's 3.25, and my French colleague hates to be kept waiting."

"I thought you were seeing Strangwise, at two?" asked Desmond.

"I put him off until six o'clock," replied the Chief, "he knows Nur-el-Din, and he may be able to give Marigold some pointers about this affair. You're off to see Miss Mackwayte now, I suppose. You know where she's staying? Good. Well, I'll say good-bye, Okewood. I shan't see you again..."

"You won't see me again? How do you mean, sir?"

"Because you're going back to France!"

"Going back to France? When?"

"By the leave-boat to-night!"

Desmond smiled resignedly.

"My dear Chief," he said, "you must be more explicit. What am I going back to France for?"

"Why, now I come to think of it," replied the Chief, "I never told you. You're going back to France to be killed, of course!"

"To be killed!"

Desmond looked blankly at the other's blandly smiling face.

"Two or three days from now," said the Chief, "you will be killed in action in France. I thought of making it a sh.e.l.l. But we'll have it a machine gun bullet if you like. Whichever you prefer; it's all the same to me!"

He laughed at the dawn of enlightenment in Desmond's eyes.

"I see," said Desmond.

"I hope you don't mind," the Chief went on more seriously, "but I know you have no people to consider except your brother and his wife. She's in America, and Francis can't possibly hear about it.

So you needn't worry on that score. Or do you?"

Desmond laughed.

"No-o-o!" he said slowly, "but I'm rather young to die. Is it absolutely necessary for me to disappear?"

"Absolutely!" responded the Chief firmly.

"But how will we manage it?" asked Desmond.

"Catch the leave-boat to-night and don't worry. You will receive your instructions in due course."

"But when shall I see you again?"

The Chief chuckled.

"Depends entirely on yourself, Okewood," he retorted. "When you're through with your job, I expect. In the meantime, Miss Mackwayte will act between us. On that point also you will be fully instructed. And now I must fly!"

"But I say, sir," Desmond interposed hastily. "You haven't told me what I am to do. What part am I to play in this business anyway?"

"To-morrow," said the Chief, b.u.t.toning up his coat, "you become Mr. Basil Bellward!"

CHAPTER VIII. THE WHITE PAPER PACKAGE

A taxi was waiting in Pall Mall outside the club and Desmond hailed it, though secretly wondering what the driver would think of taking him out to Seven Kings. Rather to his surprise, the man was quite affable, took the address of the house where Barbara was staying with her friends and bade Desmond "hop in."

Presently, for the second time that day, he was heading for the Mile End Road.

As they zigzagged in and out of the traffic, Desmond's thoughts were busy with the extraordinary mission entrusted to him. So he was to sink his own ident.i.ty and don that of an Anglo-German business man, his appearance, accent, habits, everything. The difficulties of the task positively made him cold with fear. The man must have relations, friends, business acquaintances who would be sufficiently familiar with his appearance and manner to penetrate, at any rate in the long run, the most effective disguise. What did Bellward look like? Where did lie live? How was he, Desmond, to disguise himself to resemble him? And, above all, when this knotty problem of make-up had been settled, how was he to proceed? What should be his first step to pick out from among all the millions of London's teeming populace the one obscure individual who headed and directed this gang of spies?

Why hadn't he asked the Chief all these questions? What an annoying man the Chief was to deal with to be sure! All said and done, what had he actually told Desmond? That there was a German Secret service organization spying on the movements of troops to France, that this man, Basil Bellward, who had been arrested, was one of the gang and that the dancer, Nur-el-Din, was in some way implicated in the affair! And that was the extent of his confidence! On the top of all this fog of obscurity rested the dense cloud surrounding the murder of old Mackwayte with the unexplained, the fantastic, clue of that single hair pointing back to Nur-el-Din.

Desmond consoled himself finally by saying that he would be able too get some light on his mission from Barbara Mackwayte, whom he judged to be in the Chief's confidence. But here he was doomed to disappointment. Barbara could tell him practically nothing save what he already knew, that they were to work together in this affair. Like him, she was waiting for her instructions.

Barbara received him in a neat little suburban drawing-room in the house of her friends, who lived a few streets away from the Mackwaytes. She was wearing a plainly-made black crepe de chine dress which served to accentuate the extreme pallor of her face, the only outward indication of the great shock she had sustained.

She was perfectly calm and collected, otherwise, and she stopped Desmond who would have murmured some phrases of condolence.

"Ah, no, please," she said, "I don't think I can speak about it yet."