The next thing I remember is finding myself at the door of Room 18, my fingers on the door knob, my breath coming in gasps and my heart literally in my throat.

What would the opening of that door disclose?

I took a long, shuddering breath, pushed open the door and took a few steps forward.

Intense blackness met my eyes, but through it I heard scraping sounds and heavy breathing and the impact of flesh against flesh, and the indescribable sounds of two bodies struggling together. Instinctively I stepped inside the room, closed the door behind me, and felt along the wall for the electric button.

And at that instant a vivid flash of lightning lit up the room and I caught a glimpse of two men interlocked and swaying and I heard O’Leary’s hoarse whisper.

“Don’t⁠—turn on⁠—the lights! Don’t⁠—” the rest was lost.

I stood there as if frozen to the spot, longing to take a hand in things and not daring to do so. Then all at once someone said breathlessly:

“O’Leary!”

“Yes.”

“Hell.”

The men seemed to fall apart.

“All right, then! Here it is!” The words were whispered in a panting voice that I did not recognize.

Then I felt rather than saw that the slighter of the two figures tiptoed to the window next to the bed, peered through the dashing of rain outside for a moment, and then tiptoed as cautiously back.

“Into that corner! There, back of the screen! Miss Keate?”

“Yes.”

“Over here, quick!”

I stumbled a little as I passed the foot of the bed, found a hand outstretched in the darkness to guide me, and in a flash was in the darkest corner of the room, behind the burlap screen.

“Be quiet!” warned O’Leary sternly.

Beside me, breathing quickly, was that other man; as I shrank back a little I came in contact with something cold, touched it tentatively with my fingers and drew back, chilled. It was square and hard and pressing into the coat of the man at my side. It must be held in O’Leary’s hand.

And I was standing within an inch of the thing. I must have made a sudden movement for O’Leary whispered sharply again: “Hush!”

As if petrified, the three of us stood behind that burlap screen. There was not a sound in the room. As my eyes became adjusted to the darkness I found that the window near the bed was faintly visible through the crack in the screen and I glued my gaze to that crack.

Once the man at my side stirred a little and then quieted abruptly, and I had no doubt that that menacing revolver was thrust closer into his ribs.

Just as I felt that my lungs were bursting I became aware that there was a shadow, deeper than the surrounding shadows, there at the window. I blinked and peered closer. Yes, I was sure. Silently, with amazing lack of sound it crept from the window sill into the room, paused for a second and then, so silently that it did not seem to be anything human, it glided across the room and out of my little angle of vision.

Then I was aware that O’Leary was gone and simultaneously I heard a sound like the creaking of a bed spring and O’Leary’s voice, cold and hard as that vicious revolver.

“Stand where you are! Hands up! Turn on the light, Miss Keate. Hands up! I’ve got you!”

Turn on the light!

Cross that room to the door? No, here was the light above the bed! Where was the cord! Ah! My fingers grasped it, pulled convulsively and light flooded the room.

There was a muffled exclamation from the closet door. A man standing there flung his hands over his head. O’Leary was standing on the high, narrow bed, his revolver covering the room. The man behind the screen was still motionless.

“All right, O’Brien,” said O’Leary very quietly, without moving his head.

“All right,” echoed a voice at the window. There was O’Brien’s head at the window and along the sill gleamed the barrel of another revolver, and then another as a stalwart policeman loomed up beside O’Brien.

My head cleared and my eyes stopped blinking in the sudden light.

The man at the closet door was Dr. Fred Hajek. His face was putty-coloured. His small eyes gleamed like a frightened animal’s. His raincoat dripped moisture in a little puddle on the floor.

“Got him covered, O’Brien?” said O’Leary cheerfully.

“Right!” said O’Brien.

O’Leary leaped lightly from the bed, strode over to the burlap screen, and pulled it back.

Jim Gainsay stood there, his cap pulled low over his eyes, his lean jaw set. One hand was thrust into the pocket of his coat, and the other grasped a small, square box. At the sight of the box I gasped something and pointed.

“The⁠—the radium!”

“It’s you, is it?” said O’Leary in a strange voice.

Hajek made a sudden movement; O’Leary whirled.

“Stop that!” his voice cracked like a whip. Hajek, with a furious glance at the men in the window, subsided.

O’Leary turned again, walked to the middle of the room and paused, looking from one man to the other with a curious expression in his eyes.

“Well,” he said. “I’ve got you both.”

Gainsay started to speak and stopped as the nose of one of the revolvers shifted restlessly.

“Put down your hands if you want to, Hajek,” said O’Leary easily. “Or⁠—wait a moment.”

He crossed to him, ran his hands quickly over Hajek’s pockets, unheeding the fury in those little eyes, extracted a small revolver and tossed it on the bed and smiled.

“There you are, Doctor,” he said politely. “You may lower your hands, now.”

There was a slight commotion at the window.

“Here’s somebody, Mr. O’Leary,” said someone. “He was in the shrubbery and you said not to let anybody get away.”

O’Leary peered into the little group at the window, then his eyes lightened.

“Oh, it’s you, Dr. Balman. You came at just the right time. I think we have bagged our birds. Can you come through the window, Doctor?”

It was Dr. Balman, sure enough, water running off his shoulders and shining in the light as he crawled through the window assisted by the policeman.

Once inside the room Dr. Balman looked slowly about him.

“What is this? What have you found, O’Leary?” His puzzled gaze found the box in Gainsay’s hand. He started. “Why⁠—why is that the radium?”

“It may interest you to know, Dr. Balman, that we have caught the murderer and thief.”

“What!” cried Dr. Balman. His eyes travelled slowly around the room and his voice broke a little as he cried: “Not⁠—not Fred Hajek?”

O’Leary’s keenly exultant eyes softened a little.

“Wait,” he said. “There is another in the room.”

Taking a key from his pocket, he crossed lightly to the closed door of the further closet, unlocked it and swung it open. I took a step forward and cried out involuntarily. Instantly I recognized my own purple hat, sodden and drenched, and then, cramped in that small space, a woman’s huddled figure. It was Corole!

As we stared she glared back at us for a moment. Then she rose slowly, struggling with cramped muscles. Her eyes, narrow with hate, were fixed on Lance O’Leary.

“I’ve been there for hours,” she said in a strange voice that was hoarse and strained with fury. She stamped her feet to start circulation and flexed her arms slowly. Then she pulled my hat from her head, tossed it contemptuously out of the way and ran her brown hands through her tossed, yellow hair. “You are going to suffer for this,” she said. “How dare you force me into that closet, lock the door and leave me!” She took a tigerish step or two toward O’Leary, her nails gleaming suggestively.

“Not so fast, my lady,” interposed O’Brien, who had slipped silently through the window. Corole shifted her malignant gaze, regarded O’Brien for a moment, then slowly and malevolently swept the room.

“So you are here, too?” she said to me. “And Dr. Balman. And Jim. Quite a family party.”

“You are right,” agreed O’Leary smoothly. “Quite a family party. In fact, we need only one more to make our circle complete. Miss Keate, will you please summon Miss Day?”

My heart leaped again as I heard the name, and I heard Jim Gainsay mutter something that was quickly silenced. I opened the door and slid into the corridor; there was no need to call Maida, for there she was, standing opposite the dark door above which still gleamed that ominous red light. She was very white but said nothing as I beckoned her inside the room.

At our entrance O’Leary became active. He motioned to the available chairs.

“Sit down, Miss Day⁠—Miss Keate. Dr. Balman, there is a place on the bed. We may as well make ourselves comfortable for I have a story to tell.”

I suppose my eyes went in some anxiety to the precious box in Jim Gainsay’s hand that was the cause of it all, for O’Leary smiled a bit grimly.

“Don’t be alarmed, Miss Keate. The radium is not in that box; I took it immediately to⁠—a safe place. The box over there was only a bait.”

With a disgusted exclamation Jim Gainsay dropped the box and folded his arms. His eyes sought Maida’s but she did not return his gaze.

“Well, Dr. Hajek,” said O’Leary. “It is too bad it has turned out this way. I thought better of you.”

Dr. Hajek lifted his lip in something very like a snarl but said nothing. Corole made a sudden movement which she checked under O’Leary’s regard.

“Are you sure it was Dr. Hajek? Tell me about it, O’Leary.” The ring of authority was manifest in Dr. Balman’s weary tones.

“In my own way,” promised O’Leary with an apologetic glance toward Dr. Balman. “In the first place, the superstition which so unpleasantly impressed you, Miss Keate, has been fulfilled again.” He paused dramatically, and from somewhere in the room came a sharp sigh of suspense. “The murderer of Jackson was near by when you saw blood flowing from that small wound. But he was in⁠—that closet.” He pointed. The silence breathed a question that none of us dared speak.

“Yes,” said O’Leary, answering the unspoken inquiry. “Yes. It was Dr. Letheny.”

“Dr. Letheny!” cried Jim Gainsay.

“Not⁠—not Dr. Letheny,” faltered Dr. Balman.

“It was Dr. Letheny,” repeated O’Leary quietly.

“I knew it!” cried Corole. “I knew it!”

No one looked at her. Our eyes were without exception fastened upon O’Leary’s face.

“How do you know?” I said at last.

O’Leary glanced about the room in indecision, then he shrugged.

“As well here as anywhere,” he said. “How did I know that it was Letheny? Why did not Higgins rouse the place? Because he saw the head doctor in this room. Why was there need to hunt for the radium? Because that man who hid the stuff was dead; Dr. Letheny, disturbed about the ugly business, afraid of being caught with it in his possession, hid the thing in the loud speaker, thinking no one saw him. And only Higgins knew where it was, and Higgins, terrified at what he had seen, was afraid to tell for he knew that someone⁠—someone had come upon Letheny and killed him and Higgins hoped to escape the same fate. And since there were⁠—others desiring the radium, a hunt was made for it. A search that was finally successful.” His clear gray eyes went from Corole to Hajek.

“But just as Dr. Letheny was about to leave the room another man came upon the scene, determined to take the radium for himself. Then⁠—I don’t know exactly what happened but the two men struggled and in the struggle Dr. Letheny’s head struck with such force that it killed him⁠—this”⁠—he crossed the room to the massive, square-cornered lavatory. “I am sure of that,” went on O’Leary, “for I examined it before a thing in the room had been touched. The other man, frightened perhaps, knowing that he was in desperate danger of being charged with murder, dragged Dr. Letheny’s body into that closet, locked the door and got rid of the key, hoping to postpone the discovery of Dr. Letheny’s death for as long as possible and thus cover his own tracks. But first he found that the radium was not to be found and knew that Letheny must have hidden it somewhere in the room. He did not dare search for it then, he would have to return. He retreated by the way he had come, through the window, there, and⁠—and crawled through the window of his own room in the hospital in time to answer Miss Keate who, by that time, was pounding on the door.”

His eyes went to Dr. Hajek, whose face was quite ghastly.

O’Leary forestalled the words on Dr. Hajek’s lips.

“Not now,” he said sternly. “You will have plenty of time to talk⁠—later.”

“Then⁠—then you feel sure it was Dr. Letheny who killed Jackson?” asked Dr. Balman incredulously.

“Positive,” said O’Leary. “As further proof, the revolver that belongs to Miss Letheny bears Dr. Letheny’s finger prints. Why should he bring a revolver to a hospital if his errand was entirely peaceful? He wanted the radium, he needed the money⁠—I honestly believe that the man wanted the money for research.” There was a shade of pity in O’Leary’s voice. “And as to the mechanics of the situation, Dr. Letheny must have made up his mind quite suddenly to secure the radium for his own use; he came to St. Ann’s⁠—I wonder what his feelings were when he examined the patient whom he was soon to rob, I do not think the murder was intentional⁠—then, presumably he left. Outside the hospital he accidentally came upon Miss Day and detained her for some time⁠—er⁠—seizing her sleeve as she attempted to return to the wing, and in so doing detached her cuff link. Is that right, Miss Day?”

Without a word Maida nodded assent but her deep, blue eyes shot a glance of gratitude toward the young detective.

“Then, determining to carry out his hastily formed plan for stealing the radium, he watched his chance and while Miss Day was busy in the kitchen and Miss Keate was detained for some fifteen minutes in⁠—Room 11?”

“Room 11,” I said.

“⁠—he must have slipped along the corridor into the drug room and helped himself to morphine tablets and hypodermic needle and hurried back, unseen, to Room 18. Jackson very likely never knew what happened, but Dr. Letheny was safe because, in the first place, Jackson was not surprised at the presence of his doctor and would have had no occasion to object to a hypodermic injection, and furthermore, on waking from a drugged sleep, impressions immediately preceding that sleep are vague and confused and could scarcely be given as evidence. I do not believe that Dr. Letheny intended to make the dose fatal; I believe he only intended that Jackson should know nothing of the radium being removed, but in his natural excitement Dr. Letheny either misjudged the dose he was giving or the resistive powers of his patient, with the result that we know. Dr. Letheny tossed the needle through the open window, where it was later found. In the main, I believe I am right; there may be slight discrepancies. One can’t be absolutely sure when both⁠—er⁠—participants are dead.”

There was a moment of tense silence. Then Corole spoke.

“So it was Louis,” she said in a tone of ugly satisfaction. “I knew it. I knew it all along for I watched⁠—” She checked herself.

O’Leary turned sharply.

“Just a moment,” he said coldly. “Your skirts are not entirely clear. There is Higgins’s death yet to explain, and the theft of the radium.”

“I knew nothing about Higgins’s death,” cried Corole.

“Go on, Mr. O’Leary,” begged Dr. Balman. Under the light his face looked drawn and aged.

“From that night on the struggle has been for the discovery and possession of the radium. It was thought, by those who knew of Dr. Letheny’s participation in the affair, to be still in Room 18. Hajek was determined to find it, even going so far as to steal the key to the south door in order to effect an entrance at any time.”

Again Dr. Hajek made an inarticulate murmur which O’Leary silenced.

“Becoming impatient at his continued failure to locate the radium, Miss Letheny herself, who was in⁠—er⁠—in cahoots with Hajek, took a hand in the matter. Knowing what had happened in the room and being by nature extremely superstitious, she was intensely frightened when upon entering Room 18 in the middle of the night in order to make a search for the radium herself, she saw a sheeted figure on the bed. She, too, failed to find the radium.”

“You are perfectly right about that,” said Corole brazenly. “But you are wrong about⁠—”

“Then one night Hajek grew desperate; he wanted the radium and Corole⁠—that is, Miss Letheny⁠—was reproaching him for his continued failure to find the radium. He recalled the circumstance of the electric-light connection having been damaged by lightning on the night of June seventh, decided that that condition was a valuable help and, repeated, would aid him in making a thorough and prolonged search in Room 18. So he went to the basement, disconnected the electric current, let himself out the grade door, ran around the corner of the hospital, entered the south wing by the unlocked south door, for the windows were bolted, and was into Room 18 in about a minute and a half after he pulled the light switch. Either from reflection or because he had exhausted all the other available hiding places, he went at once to the loud speaker, which by an odd circumstance was the original speaker that was in Room 18 the night of the seventh. But Higgins, in the basement, saw him and followed him. Higgins came upon him in Room 18. As I say, Hajek had at last found the radium and at the knowledge of someone witnessing his theft he shot wildly in the dark, the bullet killing Higgins instantly. Likely Higgins had said something, indicated in some way that he knew what Hajek was about and what he had taken from that loud speaker. I don’t know how it happened that Higgins got up courage enough to follow and threaten Hajek with exposure, but he evidently did. Hajek, frightened at the consequence of his deed, simply acted from primitive impulse; if he were caught on his way from the hospital the possession of the radium would be a distinctly incriminating fact, no matter how he tried to explain it away. He had only a few seconds in which to act, and he followed Dr. Letheny’s example, hiding the radium in the first place that came to hand which was⁠—a flower pot. He scooped out the dirt, thrust the box into the aperture and the soil in his pocket and hurried from the wing, around the hospital, in the basement door and to his room⁠—where we found him later. He had barely time to get to his room unobserved.”

“I didn’t! You are lying! I didn’t!” cried Dr. Hajek, his face livid and those glaring eyes going from one to the other of us. “I tell you I didn’t!”

At a motion from O’Leary, O’Brien stepped closer to Hajek, thrusting the revolver he held close to Hajek’s ribs.

“But⁠—but the mud on the window casing,” I began, bewildered. “If he used the grade door and came up by the basement⁠—”

O’Leary interrupted me.

“Miss Day happened on the radium in the pot of lobelias; it was in the corridor where Hajek had placed it in his hurry, knowing that Room 18 would be thoroughly searched. Miss Keate in the meantime⁠—I think we need not go into that. Anyway it came thus to my hands for a moment or two before Hajek knocked me senseless and took the radium. He had managed, from his room off the general office, to hear Miss Keate’s announcement and must have watched until she gave it to me⁠—”

“I’ll admit to that,” cried Dr. Hajek. “But not to that oth⁠—”

“There, there!” O’Brien poked him suggestively and Hajek stopped talking.

“But,” began Dr. Balman uncertainly, “I never dreamed it was Dr. Hajek. Why he was right there with me when we found you, O’Leary, there by the stairs. He seemed as astonished as I was.” Dr. Balman reached unsteadily for his handkerchief and passed it over his forehead. “This is terrible, O’Leary, terrible.” His voice shook. “Do you realize that you are accusing a doctor of St. Ann’s of unspeakable crimes? That you are⁠—”

“Truth is truth.” There was a queer, icy look in O’Leary’s gray eyes. “If a doctor of St. Ann’s is guilty, he is as guilty as any other man would be.”

“Oh, yes. Yes, I suppose so,” agreed Dr. Balman, reluctantly. “But it is no less⁠—terrible.” He shuddered visibly.

I found my tongue.

“Then what part has Mr. Gainsay in all this?”

O’Leary eyed me curiously before replying. Then he turned to Jim Gainsay.

“Gainsay,” he said slowly, “is a young man who is going to get into serious trouble sometime through not minding his own business. He is incurably inquisitive and has been quite sure that he and he alone could solve this mystery.” There was a gleam of mirth back of those clear, gray eyes.

Jim straightened up, felt absently in his pocket and drew out a pipe, which he held without lighting, the policeman at the window watching him with an impassive countenance.

Jim sighed.

“I am a fool,” he admitted abruptly. “But, Lord, it didn’t seem to me that you were getting anywhere. I had to take a hand in it. I thought the first thing to do was to find the radium.”

Corole’s slitted eyes flashed green fire.

“You nearly got it, too,” she said viciously. “But I got away from you.”

“Where did you hide it when Hajek turned it over to you immediately after stealing it from me?” asked O’Leary mildly.

Corole’s face was sullen but she replied, taking, I think, a certain pleasure in being the centre of the stage for a moment.

“I dug a hole under one of the trees out there,” she motioned with a long, brown hand, on which the topaz shone, toward the orchard. “I left it there all day yesterday⁠—I mean, day before yesterday.” She glanced at the window, which was beginning to show a dim, gray light. “And then that night I got away from you,” she looked at O’Brien⁠—“and you”⁠—at Jim, this time⁠—“and got it out and brought it here in my jewel case. I thought it would be safe in this room and Sarah was so excited”⁠—she cast a malicious glance toward me⁠—“she never noticed that I came out without my jewel case when she so thoughtfully took me to her room and locked me in! How did you find it?”

O’Leary did not reply.

“When Miss Letheny returned for the radium about eleven o’clock tonight I⁠—er⁠—detained her.” O’Leary glanced toward the closet from which she had emerged. “I am interested to hear that you admit to having the radium in your possession.”

“What can you do about it?” flashed Corole insolently. “And you are all wrong about Dr. Hajek. I know that he did not shoot Higgins and I know that he did not kill Louis for he was with me both times⁠—”

“That will do, Miss Letheny. Or rather, Mrs. Hajek.”

Corole started. Her brown hands clutched at the wall back of her.

“How did you know that?”

O’Brien cleared his throat self-consciously and at the sound Corole whirled to face him.

“I suppose you were following us this afternoon,” she said vindictively.

“They were married this afternoon,” said O’Leary. “Owing to a conversation overheard by one of us”⁠—I daresay it was my turn to look self-conscious⁠—“we have reason to think that possibly the bride was a bit reluctant, but however that was, they were actually married at the courthouse with Mr. O’Brien⁠—near at hand. Your own desire to perjure yourself, Mrs. Hajek, will not be of any help in the matter, for your husband cannot be cleared.”

A strange silence fell; the torrents of rain seemed to be lessening slightly and I heard a roll of thunder away off in the distance.

I was engaged in going over and over to myself O’Leary’s explanations; it did not seem to me that he had covered everything, and I was about to inquire into certain matters when O’Leary spoke again.

“Is everything clear to you, Dr. Balman?” he asked deferentially.

Dr. Balman hesitated.

“I don’t know,” he said with a puzzled and worried air. “I really don’t know. This is”⁠—he paused to pass his hand across his eyes, rubbing the bruise on his cheekbone a little as if it itched⁠—“this is a terrible responsibility, Mr. O’Leary.”

O’Leary nodded.

“But you are head of St. Ann’s,” said O’Leary. “And while the case belongs to the state to prosecute, still I should like to feel that you, as head of the institution of St. Ann’s⁠—are satisfied with our findings.”

“It doesn’t seem⁠—it doesn’t seem possible,” said Dr. Balman.

O’Leary looked obviously irritated, but said with restrained impatience:

“Is there anything that I have overlooked, Dr. Balman?”

“No. No, I suppose not,” Dr. Balman replied uncertainly.

“Perhaps I have not made myself perfectly clear,” said O’Leary, still patiently. “Let’s begin at the beginning again, Dr. Balman, and piece things out in their logical order. I want to be sure that it is all clear to you.”

“No, no! That will not be necessary.”

“Yes,” insisted O’Leary. “You being head of St. Ann’s, Doctor, should be given every scrap of information in my power to give.”

“No, no!” said Dr. Balman. “It is very painful to me. And anyway, I think I understand. Dr. Hajek got into Room 18, just after Dr. Letheny had hidden the radium. Isn’t that it?”

O’Leary nodded and there was a quickly subdued growl of dissent from Dr. Hajek.

“The two men struggled then, and Dr. Letheny was killed in the struggle?”

Again O’Leary nodded.

“Yes, I think I understand. Still it doesn’t seem possible.” Dr. Balman regarded Dr. Hajek doubtfully.

“No,” said Lance O’Leary slowly. “It does seem strange that Miss Keate should hear nothing of it.”

“I believe she did hear something of it,” said Dr. Balman, his distressed countenance turning to me. I made some gesture of assent.

“Yes,” said O’Leary. “For don’t you remember that she came down to the end of the corridor⁠—” He left his sentence hanging in the air, and as he spoke he moved his hand slightly and I was faintly surprised to see little beads of sweat glistening on the back of it, though the night was cool. His face was quiet and composed as usual.

“Oh, yes,” said Dr. Balman. “I remember now. Strange she saw or heard nothing of all this when she opened the door of Room 18 and stood there for a moment.”

Queer how silent the room was. No one seemed to breathe.

Then Lance O’Leary’s voice broke the silence; it was tight and strange and shook a little.

“Only the murderer could know that!” He shot a glance at O’Brien. “Quick!” The last word was like the sharp lash of a whip.

I was never sure just what happened then. There was a scream as Corole flung herself upon Dr. Hajek. There was another struggle going on somewhere else. Figures blurred in rapid motion⁠—there were outcries⁠—I found myself clutching at Maida⁠—Jim Gainsay’s tall figure flashed before our eyes.

Then O’Leary’s tense voice commanded the situation.

“Right, O’Brien!” he said sharply.

Then the room seemed to clear; things resumed their normal dimensions.

I stared and rubbed my eyes and stared again.

Then my knees weakened under me and I think I screamed.

The handcuffs glittered coldly on Dr. Balman’s wrists.