The door closed behind the two men. Billy Kane lay motionless, save that, as they climbed to the street and their footsteps echoed back from the stairs, his hand, gripping his revolver, stole silently from his pocket. There was a grim whiteness around his set lips. His ears strained to catch the slightest sound from within the room, and strained to catch the last echo of those retreating footfalls. He dared not make a move until they were well away—out of earshot, say, of a revolver report. If it were fancy, if the movement of that door were only his imagination unhealthily stimulated, and unhealthily preying upon his nerves, he would at least put an end to it in short order now! The steps rang faintly back from the pavement, still more faintly, and were lost. And then Billy Kane spoke—a cold deadly monotony in his voice:

“Those boards are thin! Come out into the room with your hands up before I count three, or I’ll put a bullet through. One—two——”

There was a laugh, undisguised in its mockery, but low and musical. The door, bizarre and grotesque in its zigzag projections, due to its ingenious adherence to the natural joints in the wall boards, swung open wide, and a woman stood in the room.

“I was only waiting for your friends to go, Bundy,” she said coolly.

The revolver sagged a little in Billy Kane’s hand. He could not see her face very well, the single incandescent dangling from the ceiling was miserably inadequate, but dark eyes flashed at him out of an oval face, and the chin thrown up gave a glimpse of the contour of a full throat, ivory white—and all this was merged in the background of a slender figure clothed and cloaked in some dark material, unrelieved by a single vistage of color.

She spoke again.

“I don’t think you are quite as badly hurt as you pretend, Bundy,” she said, with a sort of icy composure. “You were out last night when I came here, and if you could prowl around the streets, I think perhaps you could manage now to get from the bed over to the door there and back again without doing yourself any serious injury. The door has been unlocked since Red Vallon went out, and it might be safer—locked.”

Billy Kane did not answer her. He got up, crossed to the door, locked it, and, returning, sat down on the edge of the bed. She had not moved from her position near the far end of the room. He became conscious that he was still holding his revolver in his hand, and he thrust the weapon quietly now into his pocket. A grim smile came and hovered on his lips. This complication, another of the ramifications of his stolen identity, he did not understand at all—except that it promised him no good. She was the author of last night’s note—she had just said as much—and the wording of that note was not reassuring as to her attitude toward him, nor was the mockery in her laugh, nor was the self-contained, almost contemptuous note of command with which she had just spoken. Who was she? What was she to the Rat, that she knew the secret of that underground tunnel, and the secret of that door?

He jerked his hand toward the chair Red Vallon had vacated.

“Sit down, won’t you?” There was a tingle of irony in his voice. His invitation was at least safe ground.

She came forward toward the table, a subtle, supple grace in her movements. Subconsciously he noted that she made no sound as she crossed the room. She was like a cat—but a very beautiful cat. He could see her face better now. The eyes were hard and unfriendly, but they were great, brown, steady eyes of unfathomable depths.

She leaned against the table.

“I prefer to stand.” There was a challenge in her tones. “What I have to say will not take long.”

Billy Kane waited. The initiative was with her. He meant it to remain so. Her small white hand, ungloved, clenched suddenly at her side until its knuckles stood out like little chalky knobs.

“You look sleeker about the face, clearer about the eyes—you beast!” There was a studied deliberation in her voice that gave the words the sting of a curling whip lash. “Perhaps you’ve been——”

“You were listening there at the door?” suggested Billy Kane imperturbably, as he reached into his pocket for a cigarette.

There was a mocking little lift to her shoulders.

“Of course! That is what I came for. I followed Red Vallon here. I supposed that you would meet at the old place, now that you are back; but since you are an invalid——” Again the shoulders lifted.

“I am afraid it hardly paid you for the trouble—to listen,” Billy Kane murmured caustically. “I’m sorry! I rather fancied I saw the door move, and you see, my illness has affected my voice, and at times I can scarcely speak above a whisper, otherwise you might have overheard——”

“I overheard enough!” She took a sudden step toward him. Her eyes were flashing now; there was a flush, angry red, mounting from the white throat, suffusing her cheeks. She raised her clenched hands. “You will die with insolence and bravado on your lips, I believe!” she cried out passionately. “How I hate you! But I’ve got you—like that”—she flung out an arm toward him, and the small clenched hand opened and then closed again, slowly, as though in its grip it were remorselessly crushing and exterminating some abhorrent thing. And then her hand was raised again, and was brushed across her eyes, and a little quiver ran through her form, and she spoke more calmly. “I overheard enough. I thought this Merxler affair would be worked to-night, and I came to tell you that you are to stop it. I came to tell you to—remember! I promise, before God, that if there is murder done to-night you will be in the hands of the police within an hour. And it’s not very far from the Tombs to the death chair in Sing Sing—Bundy Morgan.”

Billy Kane’s eyes were hidden by drooped lids. His eyes were studying with curious abstraction the pattern of the faded, greasy, threadbare strip of carpet on the floor beside the bed. Murder! The word had come with a shock that for a moment unnerved him. He had not associated anything that Red Vallon or Karlin had said with murder. They had spoken so lightly, referred to it in so humdrum a way. Murder! There was something ghastly in that lightness now. A tightness came to his lips, a horror was creeping into his soul. He was only on the verge of things, of hidden and abominable things, here in this shadow land, this night land of skulking shapes, this sordid realm of the underworld. He pulled himself together. He was the Rat—he had a part to play. He was conscious that those brown, fearless eyes were fixed on him contemptuously.

“What have I to do with it?” he muttered sullenly.

“Do with it! You!” Her voice rose, as though suddenly out of control. “You dare ask that! You, with your devil’s brains—you, who planned it all before you went away!”

The cigarette that he had lighted had gone out. He sucked at it, circling it around his lips. He was fencing now with unbuttoned foils.

“Well, you’ve said it!” There was a snarl creeping into his voice. “I’ve been away. I don’t know what they’ve done since I’ve been away.”

“You know about the will, and the sealed envelope in Merxler’s safe, and you know the combination to the safe,” she said levelly. “And that’s all you need to know to stop this from going any further.”

He laughed out shortly.

“And suppose I don’t know the combination! You don’t think I can carry a thing like that in my head forever, do you?”

“No,” she said. She smiled curiously, and one hand slipped into the bodice of her dress. “I don’t think you ever did memorize that combination. But perhaps you will recognize it again—the original in your own handwriting.” She held up a crumpled piece of paper before him, then tossed it on the table.

“Where did you get that?” he demanded roughly.

Her shoulders lifted mockingly again.

“There are other secrets in this room besides that door and the tunnel to the shed, aren’t there—Bundy?”

He eyed her now for a long minute, biting openly at his lip, his face twisted in a well-simulated ugly scowl.

“So, I’m to queer this game, am I?” he snarled suddenly. “And if I’m caught—as a snitch—they’ll tear me to pieces!”

She leaned a little forward from the table, a tense, lithe thing, and her voice came low with passion:

“We’re wasting time—and you’ve none to lose. We’ve gone over this ground before, haven’t we? It’s the one chance you have—to save yourself. Some day you won’t be able to save yourself. Some day the reckoning will come; but you will always have the hope that it won’t, and that you will always succeed in staving it off each time as you have in the past. But until that day does come the only chance you have for life is to pit your wits against the fiends like yourself that are around you. For what you have done there is no atonement—only punishment. I mean you to live in suspense, but even while that suspense lasts you will pull apart and unravel your devil’s work as fast as you knit it together. You have a chance that way! When the end comes and they get you, you know how the underworld will pay—but there is the chance—that is what holds you—and with the alternative—the police—there is no chance.”

She was breathing hard. She leaned back against the table, her hands gripped tightly at its edge.

For a moment there was silence in the room. Billy Kane’s mind was groping blindly now, as in some utter darkness. In some way, for there was no question of the genuineness of her self-assurance, her very presence here in seemingly placing herself in the Rat’s power proved that she held the Rat, and the Rat’s life and liberty in the hollow of her hand, at her beck and call. How? What was the secret of the power she possessed over him? He lighted a match nonchalantly, and, as he applied the flame to the half-burned cigarette he lifted his eyes to her through the blue haze of smoke that he blew negligently in her direction.

“Sometimes,” he said in a low, menacing tone, “people, even women, who grow troublesome, have been known in this neighborhood—to disappear.”

She laughed sharply.

“You have no time to waste in foolish words!” she warned him curtly. “You know the consequences of my—disappearance. You are at liberty to take those consequences any time you choose. But you do not like them, do you—Bundy?” She moved suddenly across the room, back to the secret door through which she had entered. “I am going now,” she said steadily. “If there is murder to-night, or if any part of that plan goes through—remember!”