"Nothing," he said firmly. "I have not been upstairs in this house in three months."
The accent of truth in his voice seemed so unmistakable that even Anderson's shrewd brain was puzzled by it. But he persisted in his attempt to wring a confession from this latest suspect.
"Before Courtleigh Fleming died—did he tell you anything about a Hidden Room in this house?" he queried cannily.
The Doctor's confident air of honesty lessened, a furtive look appeared in his eyes.
"No," he insisted, but not as convincingly as he had made his previous denial.
The detective hammered at the point again.
"You haven't been trying to frighten these women out of here with anonymous letters so you could get in?"
"No. Certainly not." But again the Doctor's air had that odd mixture of truth and falsehood in it.
The detective paused for an instant.
"Let me see your key ring!" he ordered. The Doctor passed it over silently. The detective glanced at the keys—then, suddenly, his revolver glittered in his other hand.
The Doctor watched him anxiously. A puff of wind rattled the panes of the French windows. The storm, quieted for a while, was gathering its strength for a fresh unleashing of its dogs of thunder.
The detective stepped to the terrace door, opened it, and then quietly proceeded to try the Doctor's keys in the lock. Thus located he was out of visual range, and Wells took advantage of it at once. He moved swiftly toward the fireplace, extracting the missing piece of blue-print from an inside pocket as he did so. The secret the blue-print guarded was already graven on his mind in indelible characters—now he would destroy all evidence that it had ever been in his possession and bluff through the rest of the situation as best he might.
He threw the paper toward the flames with a nervous gesture of relief. But for once his cunning failed—the throw was too hurried to be sure and the light scrap of paper wavered and settled to the floor just outside the fireplace. The Doctor swore noiselessly and stooped to pick it up and make sure of its destruction. But he was not quick enough. Through the window the detective had seen the incident, and the next moment the Doctor heard his voice bark behind him. He turned, and stared at the leveled muzzle of Anderson's revolver.
"Hands up and stand back!" he commanded.
As he did so Anderson picked up the paper and a sardonic smile crossed his face as his eyes took in the significance of the print. He laid his revolver down on the table where he could snatch it up again at a moment's notice.
"Behind a fireplace, eh?" he muttered. "What fireplace? In what room?"
"I won't tell you!" The Doctor's voice was sullen. He inched, gingerly, cautiously, toward the other side of the table.
"All right—I'll find it, you know." The detective's eyes turned swiftly back to the blue-print. Experience should have taught him never to underrate an adversary, even of the Doctor's caliber, but long familiarity with danger can make the shrewdest careless. For a moment, as he bent over the paper again, he was off guard.
The Doctor seized the moment with a savage promptitude and sprang. There followed a silent, furious struggle between the two. Under normal circumstances Anderson would have been the stronger and quicker, but the Doctor fought with an added strength of despair and his initial leap had pinioned the detective's arms behind him. Now the detective shook one hand free and snatched at the revolver—in vain—for the Doctor, with a groan of desperation, struck at his hand as its fingers were about to close on the smooth butt and the revolver skidded from the table to the floor. With a sudden terrible movement he pinioned both the detective's arms behind him again and reached for the telephone. Its heavy base descended on the back of the detective's head with stunning force. The next moment the battle was ended and the Doctor, panting with exhaustion, held the limp form of an unconscious man in his arms.
He lowered the detective to the floor and straightened up again, listening tensely. So brief and intense had been the struggle that even now he could hardly believe in its reality. It seemed impossible, too, that the struggle had not been heard. Then he realized dully, as a louder roll of thunder smote on his ears, that the elements themselves had played into his hand. The storm, with its wind and fury, had returned just in time to save him and drown out all sounds of conflict from the rest of the house with its giant clamor.
He bent swiftly over Anderson, listening to his heart. Good—the man still breathed; he had enough on his conscience without adding the murder of a detective to the black weight. Now he pocketed the revolver and the blue-print—gagged Anderson rapidly with a knotted handkerchief and proceeded to wrap his own muffler around the detective's head as an additional silencer. Anderson gave a faint sigh.
The Doctor thought rapidly. Soon or late the detective would return to consciousness—with his hands free he could easily tear out the gag. He looked wildly about the room for a rope, a curtain—ah, he had it—the detective's own handcuffs! He snapped the cuffs on Anderson's wrists, then realized that, in his hurry, he had bound the detective's hands in front of him instead of behind him. Well—it would do for the moment—he did not need much time to carry out his plans. He dragged the limp body, its head lolling, into the billiard room where he deposited it on the floor in the corner farthest from the door.
So far, so good—now to lock the door of the billiard room. Fortunately, the key was there on the inside of the door. He quickly transferred it, locked the billiard room door from the outside, and pocketed the key. For a second he stood by the center table in the living-room, recovering his breath and trying to straighten his rumpled clothing. Then he crossed cautiously into the alcove and started to pad up the alcove stairs, his face white and strained with excitement and hope.
And it was then that there happened one of the most dramatic events of the night. One which was to remain, for the next hour or so, as bewildering as the murder and which, had it come a few moments sooner or a few moments later, would have entirely changed the course of events.
It was preceded by a desperate hammering on the door of the terrace. It halted the Doctor on his way upstairs, drew Beresford on a run into the living-room, and even reached the bedrooms of the women up above.
"My God! What's that?" Beresford panted.
The Doctor indicated the door. It was too late now. Already he could hear Miss Cornelia's voice above; it was only a question of a short time until Anderson in the billiard room revived and would try to make his plight known. And in the brief moment of that resume of his position the knocking came again. But feebler, as though the suppliant outside had exhausted his strength.
As Beresford drew his revolver and moved to the door, Miss Cornelia came in, followed by Lizzie.
"It's the Bat," Lizzie announced mournfully. "Good-by, Miss Neily. Good-by, everybody. I saw his hand, all covered with blood. He's had a good night for sure!"
But they ignored her. And Beresford flung open the door.
Just what they had expected, what figure of horror or of fear they waited for, no one can say. But there was no horror and no fear; only unutterable amazement as an unknown man, in torn and muddied garments, with a streak of dried blood seaming his forehead like a scar, fell through the open doorway into Beresford's arms.
"Good God!" muttered Beresford, dropping his revolver to catch the strange burden. For a moment the Unknown lay in his arms like a corpse. Then he straightened dizzily, staggered into the room, took a few steps toward the table, and fell prostrate upon his face—at the end of his strength.
"Doctor!" gasped Miss Cornelia dazedly and the Doctor, whatever guilt lay on his conscience, responded at once to the call of his profession.
He bent over the Unknown Man—the physician once more—and made a brief examination.
"He's fainted!" he said, rising. "Struck on the head, too."
"But who is he?" faltered Miss