Arriving at the top of the flight, the proprietor of the Donegal Shades knocked at the door opening immediately from the head of the stairs. There was no answer from within. An ominous stillness seemed to pervade the place, which was totally dark, save for the dim starlight which found its way through a broken window at the end of the hall. "This is blamed strange!" muttered the man, rapping smartly again. "She can't be asleep, for it's only just now she went in." But if the strange woman whom Caleb Hook had shadowed was within and awake, she did not reply. Except the muttered words of the man beside him, not a sound fell upon the detective's ear. A strange feeling of creeping horror seemed to come over him--a wholly unaccountable feeling, something which he had never experienced before. Without being able to explain why, even to himself, he was seized with a sudden desire to penetrate behind that plain deal door, upon which his companion was still exercising his knuckles wholly without avail. Pushing the saloon-keeper to one side, he rapped smartly himself, at the same time grasping the knob in his hand. It yielded to his grasp--yielded so suddenly and unexpectedly that both the detective and P. Slattery were precipitated forward into the room. With a cry of horror bursting from his lips the saloon-keeper sprang back toward the door. "Holy Mother! what mutherin' work is this?" he ejaculated, every several hair upon his fiery pate seeming to rise with terror as he stared at the sight which met the gaze of both Detective Hook and himself. For there, stretched upon the uncarpeted boards before them, amid surroundings the most poverty stricken, lay a fearful, sickening sight, rendered more plainly visible by the light of a guttering candle standing upon a plain wooden table, which, with a bed and a chair or two, formed the sole furniture of the room. Nor was the detective scarcely less affected, for the sight which he now beheld was one calculated to move the strongest man. The strange woman whose steps he had followed through the streets lay before him in the dim light of that cheerless room--dead upon the floor. CHAPTER VIII. THE SECRET OF THE IRON DOOR. The feeling uppermost in the mind of Frank Mansfield, as handcuffed and helpless, caught under the most suspicious circumstances on the very spot where a great crime had been committed, he accompanied Officer Schneider on the short journey to New Church street station, was one of hopeless despair. What was the true meaning of these strange happenings? What has become of Cutts, of his unhappy mother, and of the two boys who had detained her beneath the church-yard wall as he himself entered the bank? He did not know. He could not form even the faintest idea. Until now the thought that Cutts had been other than sincere in his request to examine the signature book of the bank had never entered his mind, but as he began to think serious doubts found place therein.