"Then you have seen him?" I exclaimed, much surprised.

My remark caused her to hold her breath for an instant. Then she answered, rather lamely, it seemed to me:

"I saw him when the keepers brought the body to the castle."

Now, according to the account I had heard, the police had conveyed the dead man direct from the wood into Dumfries. Was it possible, therefore, that she had seen Olinto before he met with his sudden end?

I feared to press her for an explanation at that moment, but, nevertheless, the admission that she had seen him struck me as a very peculiar fact.

"You judge him to be a foreigner?" I remarked as casually as I could.

"From his features and complexion I guessed him to be Italian," she responded quickly, at which I pretended to express surprise. "I saw him after the keepers had found him."

"Besides," she went on, "the stiletto was evidently an Italian one, which would almost make it appear that a foreigner was the assassin."

"Is that your own suspicion?"

"No."

"Why?"

She hesitated a moment, then in a low, eager voice she said:

"Because I have already seen that three-edged knife in another person's possession."

"That's pretty strong evidence," I declared. "The person in question will have to prove that he was not in Rannoch Wood last evening at nightfall."

"How do you know it was done at nightfall?" she asked quickly with some surprise, half-rising from her chair.

"I merely surmised that it was," I responded, inwardly blaming myself for my ill-timed admission.

"Ah!" she said with a slight sigh, "there is more mystery in this affair than we have yet discovered, Mr. Gregg. What, I wonder, brought the unfortunate young man up into our wood?"

"An appointment, without a doubt. But with whom?"

She shook her head, saying:

"My father often goes to that spot to shoot pigeon in the evening. He told us so at luncheon to-day. How fortunate he was not there last night, or he might be suspected."

"Yes," I said. "It is a very fortunate circumstance, for it cannot be a pleasant experience to be under suspicion of being an assassin. He was at home last night, was he?" I added casually.

"Of course. Don't you recollect that when you called he chatted with you? I did some typewriting for him in the study, and we were together all the afternoon—or at least till nearly five o'clock, when we went out into the hall to tea."

"Then what is your theory regarding the affair?" I inquired, rather puzzled why she should so decisively prove an alibi for her father.

"It seems certain that the poor fellow went to the wood by appointment, and was killed. But have you been up to the spot since the finding of the body?"

"No. Have you?"

"Yes. The affair interested me, and as soon as I recognized the old Italian knife in the hand of the keeper, I went up there and looked about. I am glad I did so, for I found something which seems to have escaped the notice of the detectives."

"And what's that?" I asked eagerly.

"Why, about three yards from the pool of blood where the unfortunate foreigner was found is another small pool of blood where the grass and ferns around are all crushed down as though there had been a struggle there."

"There may have been a struggle at that spot, and the man may have staggered some distance before he fell dead."

"Not if he had been struck in the heart, as they say. He would fall, would he not?" she suggested. "No. The police seem very dense, and this plain fact has not yet occurred to them. Their theory is the same as what you suggest, but my own is something quite different, Mr. Gregg. I believe that a second person also fell a victim," she added in a low, distinct tone.

I gazed at her open-mouthed. Did she, I wondered, know the actual truth? Was she aware that the woman who had fallen there had disappeared?

"A second person!" I echoed, as though in surprise. "Then do you believe that a double murder was committed?"

"I draw my conclusion from the fact that the young man, on being struck in the heart, could not have gone such a distance as that which separates the one mark from the other."

"But he might have been slightly wounded—on the hand, or in the face—at first, and then at the spot where he was found struck fatally," I suggested.

She shook her head dubiously, but made no reply to my argument. Her confidence in her own surmises made it quite apparent that by some unknown means she was aware of the second victim. Indeed, a few moments later she said to me:

"It is for this reason, Mr. Gregg, that I have sought you in confidence. Nobody must know that I have come here to you, or they would suspect; and if suspicion fell upon me it would bring upon me a fate worse than death. Remember, therefore, that my future is entirely in your hands."

"I don't quite understand," I said, rising and standing before her in the fading twilight, while the rain drove upon the old diamond window panes. "But I can only assure you that whatever confidence you repose in me, I shall never abuse, Miss Leithcourt."

"I know, I know!" she said quickly. "I trust you in this matter implicitly. I have come to you for many reasons, chief of them being that if a second victim has fallen beneath the hand of the assassin, it is, I know, a woman."

"A woman! Whom?"

"At present I cannot tell you. I must first establish the true facts. If this woman were really stricken down, then her body lies concealed somewhere in the vicinity. We must find it and bring home the crime to the guilty one."

"But if we succeed in finding it, could we place our hand upon the assassin?" I asked, looking straight at her.

"If we find it, the crime would then tell its own tale—it would convict the person in whose hand I have seen that fatal weapon," was her clear, bold answer.

"Then you wish me to assist you in this search, Miss Leithcourt?" I said, wondering if her suspicions rested upon that mysterious yachtsman, Philip Hornby, the man to whom she was engaged.

"Yes, I would beg of you to do your utmost in secret to endeavor to discover the body of the second victim. It is a woman—of that I am certain. Find her, and we shall then be able to bring the crime home to the assassin."

"But my search may bring suspicion upon me," I remarked. "It will be difficult to examine the whole wood without arousing the curiosity of somebody—the keeper or the police."

"I have already thought of that," she said. "I will pretend to-morrow to lose this watch-bracelet in the wood," and she held up her slim wrist to show me the little enameled watch set in her bracelet. "Then you and I will search for it diligently, and the police will never suspect the real reason of our investigation. To-morrow I shall write to you telling you about my loss, and you will come over to Rannoch and offer to help me."

I was silent for a moment.

"Is Mr. Woodroffe back at the castle? I heard he was to return to-day."

"No. I had a letter from him from Bordeaux a week ago. He is still on the Continent. I believe, indeed, he has gone to Russia, where he sometimes has business."

"I asked you the question, Miss Muriel, because I thought if Mr. Woodroffe were here, he might object to our searching in company," I explained, smiling.