Intensely interested as he was in the story that Tchigorsky had to tell, Geoffrey nevertheless watched the slowly moving thread on the table. Gradually and very slowly the silken tag began to draw away from the pattern on the tablecloth, Tchigorsky following it with grim eyes.

"You find it strange?" he asked Geoffrey.

"Strange and thrilling," Geoffrey replied. "It appeals to the imagination. Some tragedy may be at the other end of that innocent-looking thread."

"There may be; there would be if I were not here. We are dealing with a foe whose cunning and audacity know no bounds. You see I have been among the foe and know something of their dealings."

A passionate anger rose up in Geoffrey as he watched the gliding thread.

"Then why not drop upon them?" he cried. "Why not produce your proofs and hand the miscreants over to the police?"

"What good would that do?" Tchigorsky replied. "Could we prove that the foe had had a direct hand in the tragedies of the past? Could we demonstrate to the satisfaction of a jury that Mrs. May and her confederates were responsible for those poisoned flowers or the bees? And if we get them out of the way there are others behind them. No, no; they must be taught a lesson; they must know that we are all-powerful. And they must feel the weight of our hands. Then the painful family scandal——"

"You are going too far," Ralph interrupted warningly.

Tchigorsky checked himself after a glance at Geoffrey.

"I am not to be told everything," he said. "Why?"

"Because we dare not," Ralph murmured. "It is not that we cannot trust you, but because we dare not."

With this Geoffrey was fain to be content. By this time the thread had left the table, and was lying on the floor.

"The other end is tied to Mrs. May's door," Tchigorsky explained. "When that door was cautiously opened, of course, the thread moved. Geoffrey, you stay here. Ralph, will you go up by the back staircase and get up to the corridor. Wait there."

"Is there danger?" Geoffrey whispered.

"Not now," said Tchigorsky, "but this audacity passes all bounds. That woman had planned to strike a blow at the very moment when she was enjoying the hospitality of this roof. The boldness of it would have averted all suspicion from her. One of the family mysteriously disappears and is never heard of again. In the morning not one lock or bolt or bar is disturbed. And yet the member of the family is gone. England would have been startled by the news to-morrow."

"You heard all this?" Geoffrey cried.

"Yes," Tchigorsky said quietly. "That disguise I showed you was useful to me. It is going to be more useful still."

"But the danger! It must be averted," Geoffrey whispered.

Already Tchigorsky was leaving the room. The lamp had been extinguished, after taking care to place a box of matches close beside it. In the darkness Geoffrey waited, tingling to his finger tips with suppressed excitement.

Meanwhile, Tchigorsky felt his way along in the darkness. He was counting his steps carefully. He reached a certain spot and then stopped. Ralph strolled down the back staircase, and thence down a flagged passage into the hall, where he climbed the stairs.

Light and darkness, it was all the same to him. There was nobody in the house who could find his way about as well as he.

Then he waited for the best part of half an hour. He could hear queer sounds coming from one of the bedrooms, a half cry in light feminine tones, a smothered protest and then the suggestion of a struggle. Yet Ralph never moved toward it; under cover of the darkness he smiled.

Then he heard a door creak and open; he heard footsteps coming along in his direction. The footsteps were stealthy, yet halting; there was the suggestion of the swish of silken drapery. On and on that mysterious figure came until it walked plump into Ralph's arms.

There was a faint cry—a cry strangled in its birth.

"Mrs. May," Ralph said quietly, "I am afraid I startled you."

The woman was gasping for breath, iron-nerved as she was. She stammered out some halting, stumbling explanation. She was suffering from nervous headache, she was subject to that kind of thing, and there was a remedy she always carried in her jacket pocket. And the jacket was in the hall.

"Go back to your room," said Ralph. "I will fetch it for you."

"There is no occasion," the woman replied. "The shock of meeting you has cured me. But what are you doing?"

"Sleeping on the stairs," Ralph said in his dullest, most mechanical way.

"Sleep—sleeping on the stairs! Why?"

"I frequently do it. I suffer from insomnia. The accident that deprived me of my sight injured my reason. This is one of my lucid intervals. For years I slept in the open air; the atmosphere of a bedroom stifles me. So I am here."

"And here you are going to remain all night?"

"Yes. I presume you have no objection."

Mrs. May was silent. Did this man know the terrible position he had placed her in? Was he telling the truth, or was he spying on her? Was he dangerous enough to be removed? Or was he the poor creature he represented himself to be?

"You should get your clever friend Tchigorsky to cure you," she said.

"Tchigorsky has gone away. I don't know when I shall see him again."

That was good news, at any rate. Mrs. May stooped to artifice. There were reasons why this man should be got out of the way at present. He had brought danger by his stupid eccentricity, but the bold woman was not going to change her plans for that.

"Be guided by me," she said. "Go to your room."

"I am here till the morning," Ralph said doggedly. "Go to yours. We are a lost, doomed race. What does it matter what I do?"

It was useless to combat sullen obstinacy like this. Mrs. May uttered a few clear words in a language that not one in a million would understand—certainly not three people in England. It never occurred to her for a moment that Ralph Ravenspur might be one of the three, but he was.

He listened grimly. No doubt the mysterious words had nothing to do with the matter, but a door in the corridor opened, and Marion emerged, carrying a light in her hand. She came swiftly down the corridor, her long hair streaming behind her. As she saw Ralph she gave a sigh of relief.

"Come quickly to Vera's room," she said. "I want your help."

In her intense excitement she seemed not to notice Mrs. May. The latter stood aside while the other two passed along. She slipped into her own room and closed the door.

"Foiled," she hissed, "and by that poor meaningless idiot. Is it possible that he suspected anything? But no, he is only a fool. If I had only dared, I might have 'removed' him at the same time. On the whole, it was a good thing that Marion did not see me."

Without the least trace of excitement and without hurry, Ralph followed Marion. A light was burning in the room and Vera, still dressed, was lying on the bed. She was fast asleep, but her face was deadly cold and her breathing was faint to nothingness. Ralph's fingers rested on her pulse for a minute.

"How long has she been like this?" Ralph asked.

"I don't know," Marion replied. "I was just dropping asleep when I fancied I heard Vera call out. In this house the mere suggestion sufficed. I crept quietly along and came in here. The room was empty save for Vera and there was no sign of a struggle. I should have imagined it to be all fancy but for the queer look in Vera's face. When I touched her I found her to be deadly cold. Is—is it dangerous?"

Ralph shook his head.

"Mysterious as ever," he said. "The miscreant is by us, almost in our hands, and yet we cannot touch him. Vera has been rendered insensible by a drug. The effect of it will pass away in time. She will sleep till morning, and you had better remain with her."

"Of course, I should not dream of leaving the poor child alone."

Ralph just touched Marion's cheek.

"You are a good girl—an angel," he murmured. "What we should do without you I cannot say. Stay here and have no fear. I shall not be far away. I am going to sleep for the rest of the night on the floor outside."

"On the floor, my dear uncle?"

"Bah! it is no hardship," said Ralph. "I have had far less comfortable quarters many a time. I am used to it and like it. And I sleep like a hare. The slightest noise or motion and I am awake instantly."

Marion raised no further protests. This singular individual was in the habit of doing as he pleased, and nothing could turn him from his humor.

He bade Marion good-night and softly closed the door. But he did not lie down at the head of the stairs. On the contrary, he crept quietly down to his room again.

There Tchigorsky and Geoffrey waited him. The lamp was once more lighted. Tchigorsky had a grin on his face.

"Foiled her?" he asked. "I heard you."

"For the present, at any rate," Ralph replied. "That charming woman does me the honor to regard me as a benighted idiot."

Tchigorsky dropped into a chair and rocked to and fro, shaking with noiseless mirth.