“You have not seen her for twelve months?”

Helen’s voice was almost inaudible, and she was trembling dreadfully.

“That’s a fact, my dear.  And now, what are we going to tell Harry Leroux?”

It was a question, the answer to which was by no means evident at a glance; and leaving Helen Cumberly face to face with this new and horrible truth which had brought Denise Ryland hotfoot from Paris to London, let us glance, for a moment, into the now familiar room of Detective-Inspector Dunbar at Scotland Yard.

He had returned from his interrogation of Brian; and he received the report of Sowerby, respecting the late Mrs. Vernon’s maid.  The girl, Sergeant Sowerby declared, was innocent of complicity, and could only depose to the fact that her late mistress took very little luggage with her on the occasions of her trips to Scotland.  With his notebook open before him upon the table, Dunbar was adding this slight item to his notes upon the case, when the door opened, and the uniformed constable entered, saluted, and placed an envelope in the Inspector’s hand.

“From the commissioner!” said Sowerby, significantly.

With puzzled face, Dunbar opened the envelope and withdrew the commissioner’s note.  It was very brief:—­

“M.  Gaston Max, of the Paris Police, is joining you in the Palace Mansions murder case.  You will cooperate with him from date above.”

“Max!” said Dunbar, gazing astoundedly at his subordinate.

Certainly it was a name which might well account for the amazement written upon the inspector’s face; for it was the name of admittedly the greatest criminal investigator in Europe!

“What the devil has the case to do with the French police?” muttered Sowerby, his ruddy countenance exhibiting a whole history of wonderment.

The constable, who had withdrawn, now reappeared, knocking deferentially upon the door, throwing it open, and announcing: 

“Mr. Gaston Max, to see Detective-Inspector Dunbar.”

Bowing courteously upon the threshold, appeared a figure in a dazzling check traveling-coat—­a figure very novel, and wholly unforgettable.

“I am honored to meet a distinguished London colleague,” he said in perfect English, with a faint American accent.

Dunbar stepped across the room with outstretched hand, and cordially shook that of the famous Frenchman.

“I am the more honored,” he declared, gallantly playing up to the other’s courtesy.  “This is Detective-Sergeant Sowerby, who is acting with me in the case.”

M. Gaston Max bowed low in acknowledgment of the introduction.

“It is a pleasure to meet Detective-Sergeant Sowerby,” he declared.

These polite overtures being concluded then, and the door being closed, the three detectives stood looking at one another in momentary silence.  Then Dunbar spoke with blunt directness: 

“I am very pleased to have you with us, Mr. Max,” he said; “but might I ask what your presence in London means?”