Lord Alloway shook his head.

"Quite impossible-they would have had to pa.s.s him in order to do so."

"And Mr. Fitzroy himself-you are sure of him, eh?"

Lord Alloway flushed.

"Absolutely, M. Poirot. I will answer confidently for my secretary. It is quite impossible that he should be concerned in the matter in any way."

"Everything seems to be impossible," remarked Poirot rather drily. "Possibly the plans attached to themselves a little pair of wings, and flew away-comme ca!" He blew his lips out like a comical cherub.

"The whole thing is impossible," declared Lord Alloway impatiently. "But I beg, M. Poirot, that you will not dream of suspecting Fitzroy. Consider for one moment-had he wished to take the plans, what could have been easier for him than to take a tracing of them without going to the trouble of stealing them?"

"There, milor'," said Poirot with approval, "you make a remark bien juste-I see that you have a mind orderly and methodical. L'Angleterre is happy in possessing you."

Lord Alloway looked rather embarra.s.sed by this sudden burst of praise. Poirot returned to the matter in hand.

"The room in which you had been sitting all the evening-"

"The drawing room? Yes?"

"That also has a window on the terrace, since I remember your saying you went out that way. Would it not be possible for someone to come out by the drawing room window and in by this one while Mr. Fitzroy was out of the room, and return the same way?"

"But we'd have seen them," objected the Admiral.

"Not if you had your backs turned, walking the other way."

"Fitzroy was only out of the room a few minutes, the time it would take us to walk to the end and back."

"No matter-it is a possibility-in fact, the only one as things stand."

"But there was no one in the drawing room when we went out," said the Admiral.

"They may have come there afterwards."

"You mean," said Lord Alloway slowly, "that when Fitzroy heard the maid scream and went out, someone was already concealed in the drawing room, and that they darted in and out through the windows, and only left the drawing room when Fitzroy had returned to this room?"

"The methodical mind again," said Poirot, bowing.

"You express the matter perfectly."

"One of the servants, perhaps?"

"Or a guest. It was Mrs. Conrad's maid who screamed. What exactly can you tell me of Mrs. Conrad?"

Lord Alloway considered for a minute.

"I told you that she is a lady well known in society. That is true in the sense that she gives large parties, and goes everywhere. But very little is known as to where she really comes from, and what her past life has been. She is a lady who frequents diplomatic and Foreign Office circles as much as possible. The Secret Service is inclined to ask-why?"

"I see," said Poirot. "And she was asked here this weekend-"

"So that-shall we say?-we might observe her at close quarters."

"Parfaitement! It is possible that she has turned the tables on you rather neatly."

Lord Alloway looked discomfited, and Poirot continued: "Tell me, milor', was any reference made in her hearing to the subjects you and the Admiral were going to discuss together?"

"Yes," admitted the other. "Sir Harry said: 'And now for our submarine! To work!' or something of that sort. The others had left the room, but she had come back for a book."

"I see," said Poirot thoughtfully. "Milor', it is very late-but this is an urgent affair. I would like to question the members of this house party at once if it is possible."

"It can be managed, of course," said Lord Alloway. "The awkward thing is, we don't want to let it get about more than can be helped. Of course, Lady Juliet Weardale and young Leonard are all right-but Mrs. Conrad, if she is not guilty, is rather a different proposition. Perhaps you could just state that an important paper is missing, without specifying what it is, or going into any of the circ.u.mstances of the disappearance?"

"Exactly what I was about to propose myself," said Poirot, beaming. "In fact, in all three cases. Monsieur the Admiral will pardon me, but even the best of wives-"

"No offence," said Sir Harry. "All women talk, bless 'em! I wish Juliet would talk a little more and play bridge a little less. But women are like that nowadays, never happy unless they're dancing or gambling. I'll get Juliet and Leonard up, shall I, Alloway?"

"Thank you. I'll call the French maid. M. Poirot will want to see her, and she can rouse her mistress. I'll attend to it now. In the meantime, I'll send Fitzroy along."

II.

Mr. Fitzroy was a pale, thin young man with pince-nez and a frigid expression. His statement was practically word for word what Lord Alloway had already told us.

"What is your own theory, Mr. Fitzroy?"

Mr. Fitzroy shrugged his shoulders.

"Undoubtedly someone who knew the hang of things was waiting his chance outside. He could see what went on through the window, and he slipped in when I left the room. It's a pity Lord Alloway didn't give chase then and there when he saw the fellow leave."

Poirot did not undeceive him. Instead he asked: "Do you believe the story of the French maid-that she had seen a ghost?"

"Well, hardly, M. Poirot!"

"I mean-that she really thought so?"

"Oh, as to that, I can't say. She certainly seemed rather upset. She had her hands to her head."

"Aha!" cried Poirot with the air of one who has made a discovery. "Is that so indeed-and she was without doubt a pretty girl?"

"I didn't notice particularly," said Mr. Fitzroy in a repressive voice.

"You did not see her mistress, I suppose?"

"As a matter of fact, I did. She was in the gallery at the top of the steps and was calling her-'Leonie!' Then she saw me-and of course retired."

"Upstairs," said Poirot, frowning.

"Of course, I realize that all this is very unpleasant for me-or rather would have been, if Lord Alloway had not chanced to see the man actually leaving. In any case, I should be glad if you would make a point of searching my room-and myself."

"You really wish that?"

"Certainly I do."

What Poirot would have replied I do not know, but at that moment Lord Alloway reappeared and informed us that the two ladies and Mr. Leonard Weardale were in the drawing room.

The women were in becoming negligees. Mrs. Conrad was a beautiful woman of thirty-five, with golden hair and a slight tendency to embonpoint. Lady Juliet Weardale must have been forty, tall and dark, very thin, still beautiful, with exquisite hands and feet, and a restless, haggard manner. Her son was rather an effeminate-looking young man, as great a contrast to his bluff, hearty father as could well be imagined.

Poirot gave forth the little rigmarole we had agreed upon, and then explained that he was anxious to know if anyone had heard or seen anything that night which might a.s.sist us.

Turning to Mrs. Conrad first, he asked her if she would be so kind as to inform him exactly what her movements had been.

"Let me see . . . I went upstairs. I rang for my maid. Then, as she did not put in an appearance, I came out and called her. I could hear her talking on the stairs. After she had brushed my hair, I sent her away-she was in a very curious nervous state. I read awhile and then went to bed."

"And you, Lady Juliet?"

"I went straight upstairs and to bed. I was very tired."

"What about your book, dear?" asked Mrs. Conrad with a sweet smile.

"My book?" Lady Juliet flushed.

"Yes, you know, when I sent Leonie away, you were coming up the stairs. You had been down to the drawing room for a book, you said."

"Oh yes, I did go down. I-I forgot."

Lady Juliet clasped her hands nervously together.

"Did you hear Mrs. Conrad's maid scream, milady?"

"No-no, I didn't."

"How curious-because you must have been in the drawing room at the time."

"I heard nothing," said Lady Juliet in a firmer voice.

Poirot turned to young Leonard.

"Monsieur?"

"Nothing doing. I went straight upstairs and turned in."

Poirot stroked his chin.

"Alas, I fear there is nothing to help me here. Mesdames and monsieur, I regret-I regret infinitely to have deranged you from your slumbers for so little. Accept my apologies, I pray of you."

Gesticulating and apologizing, he marshalled them out. He returned with the French maid, a pretty, impudent-looking girl. Alloway and Weardale had gone out with the ladies.

"Now, mademoiselle," said Poirot in a brisk tone, "let us have the truth. Recount to me no histories. Why did you scream on the stairs?"

"Ah, monsieur, I saw a tall figure-all in white-"

Poirot arrested her with an energetic shake of his forefinger.

"Did I not say, recount to me no histories? I will make a guess. He kissed you, did he not? M. Leonard Weardale, I mean?"

"Eh bien, monsieur, and after all, what is a kiss?"

"Under the circ.u.mstances, it is most natural," replied Poirot gallantly. "I myself, or Hastings here-but tell me just what occurred."

"He came up behind me, and caught me. I was startled, and I screamed. If I had known, I would not have screamed-but he came upon me like a cat. Then came M. le secretaire. M. Leonard flew up the stairs. And what could I say? Especially to a jeune homme comme ca-tellement comme il faut? Ma foi, I invent a ghost."

"And all is explained," cried Poirot genially. "You then mounted to the chamber of Madame your mistress. Which is her room, by the way?"

"It is at the end, monsieur. That way."

"Directly over the study, then. Bien, mademoiselle, I will detain you no longer. And la prochaine fois, do not scream."

Handing her out, he came back to me with a smile.

"An interesting case, is it not, Hastings? I begin to have a few little ideas. Et vous?"

"What was Leonard Weardale doing on the stairs? I don't like that young man, Poirot. He's a thorough young rake, I should say."

"I agree with you, mon ami."

"Fitzroy seems an honest fellow."

"Lord Alloway is certainly insistent on that point."

"And yet there is something in his manner-"

"That is almost too good to be true? I felt it myself. On the other hand, our friend Mrs. Conrad is certainly no good at all."

"And her room is over the study," I said musingly, and keeping a sharp eye on Poirot.

He shook his head with a slight smile.

"No, mon ami, I cannot bring myself seriously to believe that that immaculate lady swarmed down the chimney, or let herself down from the balcony."

As he spoke, the door opened, and to my great surprise, Lady Juliet Weardale flitted in.

"M. Poirot," she said somewhat breathlessly, "can I speak to you alone?"

"Milady, Captain Hastings is as my other self. You can speak before him as though he were a thing of no account, not there at all. Be seated, I pray you."

She sat down, still keeping her eyes fixed on Poirot.

"What I have to say is-rather difficult. You are in charge of this case. If the-papers were to be returned, would that end the matter? I mean, could it be done without questions being asked?"