Hercule Poirot said: "It is a little like your puzzle, Madame. One a.s.sembles the pieces. It is like a mosaic-many colours and patterns-and every strange-shaped little piece must be fitted into its own place."

"Now isn't that interesting? Why, I'm sure you explain it just too beautifully."

Poirot went on: "And sometimes it is like that piece of your puzzle just now. One arranges very methodically the pieces of the puzzle-one sorts the colours-and then perhaps a piece of one colour that should fit in with-say, the fur rug, fits in instead in a black cat's tail."

"Why, if that doesn't sound too fascinating! And are there a great many pieces, M. Poirot?"

"Yes, Madame. Almost everyone here in this hotel has given me a piece for my puzzle. You amongst them."

"Me?" Mrs. Gardener's tone was shrill.

"Yes, a remark of yours, Madame, was exceedingly helpful. I might say it was illuminating."

"Well, if that isn't too lovely! Can't you tell me some more, M. Poirot?"

"Ah! Madame, I reserve the explanations for the last chapter."

Mrs. Gardener murmured: "If that isn't just too bad!"

V.

Hercule Poirot tapped gently on the door of Captain Marshall's room. Inside there was the sound of a typewriter.

A curt "Come in" came from the room and Poirot entered.

Captain Marshall's back was turned to him. He was sitting typing at the table between the windows. He did not turn his head but his eyes met Poirot's in the mirror that hung on the wall directly in front of him. He said irritably: "Well, M. Poirot, what is it?"

Poirot said quickly: "A thousand apologies for intruding. You are busy?"

Marshall said shortly: "I am rather."

Poirot said: "It is one little question that I would like to ask you."

Marshall said: "My G.o.d, I'm sick of answering questions. I've answered the police questions. I don't feel called upon to answer yours."

Poirot said: "Mine is a very simple one. Only this. On the morning of your wife's death, did you have a bath after you finished typing and before you went out to play tennis?"

"A bath? No, of course I didn't! I'd had a bathe only an hour earlier!"

Hercule Poirot said: "Thank you. That is all."

"But look here. Oh-" the other paused irresolutely.

Poirot withdrew, gently closing the door.

Kenneth Marshall said: "The fellow's crazy!"

VI.

Just outside the bar Poirot encountered Mr. Gardener. He was carrying two c.o.c.ktails and was clearly on his way to where Mrs. Gardener was ensconced with her jig-saw.

He smiled at Poirot in genial fashion.

"Care to join us, M. Poirot?"

Poirot shook his head. He said: "What did you think of the inquest, Mr. Gardener?"

Mr. Gardener lowered his voice. He said: "Seemed kind of indeterminate to me. Your police, I gather, have got something up their sleeves."

"It is possible," said Hercule Poirot.

Mr. Gardener lowered his voice still further.

"I shall be glad to get Mrs. Gardener away. She's a very, very sensitive woman, and this affair has got on her nerves. She's very highly strung."

Hercule Poirot said: "Will you permit me, Mr. Gardener, to ask you one question?"

"Why, certainly, M. Poirot. Delighted to a.s.sist in any way I can."

Hercule Poirot said: "You are a man of the world-a man, I think, of considerable ac.u.men. What, frankly, was your opinion of the late Mrs. Marshall?"

Mr. Gardener's eyebrows rose in surprise. He glanced cautiously round and lowered his voice.

"Well, M. Poirot, I've heard a few things that have been kind of going around, if you get me, especially among the women." Poirot nodded. "But if you ask me I'll tell you my candid opinion and that is that that woman was pretty much of a darned fool!"

Hercule Poirot said thoughtfully: "Now that is very interesting."

VII.

Rosamund Darnley said: "So it's my turn, is it?"

"Pardon?"

She laughed.

"The other day the Chief Constable held this inquisition. You sat by. Today, I think, you are conducting your own unofficial inquiry. I've been watching you. First Mrs. Redfern, then I caught a glimpse of you through the lounge window where Mrs. Gardener is doing her hateful jig-saw puzzle. Now it's my turn."

Hercule Poirot sat down beside her. They were on Sunny Ledge. Below them the sea showed a deep-glowing green. Farther out it was a pale dazzling blue.

Poirot said: "You are very intelligent, Mademoiselle. I have thought so ever since I arrived here. It would be a pleasure to discuss this business with you."

Rosamund Darnley said softly: "You want to know what I think about the whole thing?"

"It would be most interesting."

Rosamund said: "I think it's really very simple. The clue is in the woman's past."

"The past? Not the present?"

"Oh! not necessarily the very remote past. I look at it like this. Arlena Marshall was attractive, fatally attractive, to men. It's possible, I think, that she also tired of them rather quickly. Amongst her-followers, shall we say-was one who resented that. Oh, don't misunderstand me, it won't be someone who sticks out a mile. Probably some tepid little man, vain and sensitive-the kind of man who broods. I think he followed her down here, waited his opportunity and killed her."

"You mean that he was an outsider, that he came from the mainland?"

"Yes. He probably hid in that cave until he got his chance."

Poirot shook his head. He said: "Would she go there to meet such a man as you describe? No, she would laugh and not go."

Rosamund said: "She mayn't have known she was going to meet him. He may have sent her a message in some other person's name."

Poirot murmured: "That is possible."

Then he said: "But you forget one thing, Mademoiselle. A man bent on murder could not risk coming in broad daylight across the causeway and past the hotel. Someone might have seen him."

"They might have-but I don't think that it's certain. I think it's quite possible that he could have come without anyone noticing him at all."

"It would be possible, yes, that I grant you. But the point is that he could not count on that possibility."

Rosamund said: "Aren't you forgetting something? The weather."

"The weather?"

"Yes. The day of the murder was a glorious day, but the day before, remember, there was rain and thick mist. Anyone could come on to the island then without being seen. He had only to go down to the beach and spend the night in the cave. That mist, M. Poirot, is important."

Poirot looked at her thoughtfully for a minute or two. He said: "You know, there is a good deal in what you have just said."

Rosamund flushed. She said: "That's my theory, for what it is worth. Now tell me yours."

"Ah," said Hercule Poirot. He stared down at the sea.

"Eh bien, Mademoiselle. I am a very simple person. I always incline to the belief that the most likely person committed the crime. At the very beginning it seemed to me that one person was very clearly indicated."

Rosamund's voice hardened a little. She said: "Go on."

Hercule Poirot went on.

"But you see, there is what you call a snag in the way! It seems that it was impossible for that person to have committed the crime."

He heard the quick expulsion of her breath. She said rather breathlessly: "Well?"

Hercule Poirot shrugged his shoulders.

"Well, what do we do about it? That is my problem." He paused and then went on. "May I ask you a question?"

"Certainly."

She faced him, alert and vigilant. But the question that came was an unexpected one.

"When you came in to change for tennis that morning, did you have a bath?"

Rosamund stared at him.

"A bath? What do you mean?"

"That is what I mean. A bath! The receptacle of porcelain, one turns the taps and fills it, one gets in, one gets out and ghoosh-ghoosh-ghoosh, the water goes down the waste pipe!"

"M. Poirot, are you quite mad?"

"No, I am extremely sane."

"Well, anyway, I didn't take a bath."

"Ha!" said Poirot. "So n.o.body took a bath. That is extremely interesting."

"But why should anyone take a bath?"

Hercule Poirot said: "Why, indeed?"

Rosamund said with some exasperation: "I suppose this is the Sherlock Holmes touch!"

Hercule Poirot smiled.

Then he sniffed the air delicately.

"Will you permit me to be impertinent, Mademoiselle?"

"I'm sure you couldn't be impertinent, M. Poirot."

"That is very kind of you. Then may I venture to say that the scent you use is delicious-it has a nuance-a delicate elusive charm." He waved his hands, and then added in a practical voice, "Gabrielle, No. 8, I think?"

"How clever you are. Yes, I always use it."

"So did the late Mrs. Marshall. It is chic, eh? And very expensive?"

Rosamund shrugged her shoulders with a faint smile.

Poirot said: "You sat here where we are now, Mademoiselle, on the morning of the crime. You were seen here, or at least your sunshade was seen by Miss Brewster and Mr. Redfern as they pa.s.sed on the sea. During the morning, Mademoiselle, are you sure you did not happen to go down to Pixy Cove and enter the cave there-the famous Pixy's Cave?"

Rosamund turned her head and stared at him.

She said in a quiet level voice: "Are you asking me if I killed Arlena Marshall?"

"No, I am asking you if you went into the Pixy's Cave?"

"I don't even know where it is. Why should I go into it? For what reason?"

"On the day of the crime, Mademoiselle, somebody had been in that cave who used Gabrielle No 8."

Rosamund said sharply: "You've just said yourself, M. Poirot, that Arlena Marshall used Gabrielle No. 8. She was on the beach there that day. Presumably she went into the cave."