She nodded tolerantly.  “Why keep up the fiction?” she asked.  “You know that I am concerned in your adventure—­just as I know of your adventure.  I was on the street, or in the house, or was told of it, whichever you please; it’s all one, since you know.  Moreover you have seen me with one of your early morning callers, as I meant you to do.”  She leaned forward and looked at him with half-closed eyes.  “Will you believe me, Guy, when I say that the United States is not concerned in the matter—­and that it should keep its hands off.  You stumbled by accident on the deserted cab.  A subordinate blundered, or you would not have found it ready for your investigation—­and you’ve been unduly and unnecessarily inquisitive.  We have tried to be forbearing and considerate in our efforts to regain it, but—­”

“Regain, my dear Madeline, implies, or at least it conveys an idea of, previous possession.  Did Germany—­I beg your pardon; did your client in this matter have such—­”

“I used regain advisedly,” she broke in.

“Because of your possession of the lady, or because of your independent possession of the letter?”

“You’re pleased to be technical,” she shrugged.

“Not at all!” he replied.  “I’m simply after the facts:  whether the letter belongs to you, or to the mysterious lady of the cab?”

“Who isn’t in the least mysterious to you.”

“No!”

“Really, you’re delicious, Mr. Harleston; though I confess that you have me mystified as to your game in pretending what you and I know is pretence.”

“You’re pleased to be enigmatic!” Harleston laughed.

“Oh, no I’m not,” she smiled, flashing her rings and watching the flashes—­and him.  “You saw me, and you know that I saw you; and I saw you and know that you saw me.  Now, as I’ve said it in words of one syllable, I trust you will understand.”

“I understand,” said he; “but you have side-stepped the point:—­To whom does this lost letter belong:  to you or to—­”

“Mrs. Clephane?” she adjected.

“Exactly:  to you, or to Mrs. Clephane?”

“What does that matter to you—­since it does not belong to you?”

“I may be a friend of Mrs. Clephane?  Or I may regard myself as a trustee for the safe delivery of the letter.”

“A volunteer?”

“If you so have it!” he smiled.

She beat a tattoo with her slender, nervous fingers, looking at him in mild surprise, and some disapproval.

“Since when does sentiment enter the game?” she asked.

“Sentiment?” he inflected.  “I wasn’t aware of its entry.”

She shrugged mockingly.  “Beware, old friend and enemy!  You’re losing your cleverness.  Mrs. Clephane is very charming and alluring, but remember, Guy, that a charming woman has no place in the diplomatic game—­save to delude the enemy.  She seems to be winning with you—­who, I thought, was above all our wiles and blandishments.  Oh, do not smile, sir—­I recognize the symptoms; I’ve played the innocent and the beauty in distress once or twice myself.  It’s all in our game—­but I’m shockingly amazed to see it catch so experienced a bird as Guy Harleston.”