“Well,” Desmond went on deliberately, “I think that story gives us the right measure of Nur-el-Din’s, character. She may be vain, she may be without morals, she may be weak, she may be an adventuress, but she’s not a murderess. If anything, she’s a victim!”

Francis laughed shortly.

“Victim be damned!” he cried. “Man alive,” he went on, “how can you talk such nonsense in face of the evidence, with this bloody-minded woman’s victims hardly cold yet? But, horrible as these murders are, the private squabbles of this gang of spies represent neither your interest nor mine in this case. For us the fact remains that Nur-el-Din, besides being a monster of iniquity, is the heart and soul and vitals of the whole conspiracy!”

Jaded and nervous, Desmond felt a quick sting of resentment at his brother’s tone. Why should Francis thus lay down the law to him about Nur-el-Din? Francis knew nothing of the girl or her antecedents while he, Desmond, flattered himself that he had at least located the place she occupied in this dark conspiracy. And he cried out vehemently:

“You’re talking like a fool! I grant you that Nur-el-Din has been mixed up with this spy crowd; but she herself stands absolutely apart from the organization...”

“Half a minute!” put in Francis, “aren’t you forgetting that blue envelope we took off her just now?”

“What about it?” asked Desmond sharply.

“Merely this; the cipher is in five figure groups, addressed to a four figure group and signed by a six figure group...”

“Well?”

“That happens to be the current secret code of the German Great General Staff. If you were to tap a German staff message out in France to-day, ten to one it would be in that code. Curious coincidence, isn’t it?”