“There are quite too many women in this affair,” Harleston commented.  “However, the Burlingame is almost directly across the street from where I found the cab, so her story will be interesting—­if it’s not a plant.”

“And it may be even more interesting if it is a plant,” Ranleigh added.  “If you will come in a bit before three, I’ll put you where you can see and hear everything that takes place.”

“I’ll do it!” said Harleston.

VI

THE GREY-STONE HOUSE

Harleston returned at a quarter to three, and Ranleigh showed him into the small room at the rear, provided with every facility for seeing what went on and overhearing and reducing what was said in the Superintendent’s private office.

Promptly at three, Mrs. Winton was announced by appointment, and was instantly admitted.

She was about thirty years of age, slender, with dark hair and a face just missing beauty.  She was gowned in black, with a bunch of violets at her waist, and she wore a large mesh veil, through which her particularly fine dark eyes sparkled discriminatingly.

The Superintendent arose and bowed graciously.  Ranleigh was a gentleman by birth and by breeding.

“What can I do for you, Mrs. Winton?” he asked, placing a chair for her—­where her face would be in full view from the cabinet.

“You can do nothing for me, sir,” she replied, with a charming smile.  “I came to you as head of the Police Department for the purpose of detailing what I saw in connection with the matter I mentioned to you over the telephone.  It may be of no value to you—­I even may do wrong in volunteering my information, but—­”

“On the contrary,” the Superintendent interjected, “you confer a great favour on this Department by reporting to it any suspicious circumstances.  It is for it to investigate and determine whether they call for action.  Pray proceed, my dear Mrs. Winton.”

She gave him another charming smile and went on.

“I was out last evening, and it was after midnight when I got back to the Burlingame.  My apartment is on the third floor front.  Instead of going to bed at once, I sat down at the open window to enjoy the gentle breeze.  I must have dozed, for I was aroused by a cab coming up Eighteenth and stopping before the large, grey-stone house opposite—­the rest of the houses are brick—­which was unoccupied until two days ago, when it was rented furnished.  I live just across the street and hence I notice these things—­casually of course, as one does.  I watched the cab with languid interest; saw the driver descend from the box, which seemed a bit peculiar; but when, instead of going to the door of the cab, he went up the front steps and into the house—­the door of which he opened with a key that he took from his pocket—­my curiosity was aroused.  A moment later, a man in evening dress came leisurely