Sleeping Murder by Agatha Christie

looking.'
    'Come out and see the garden,' said Gwenda.
    They showed her the house and the garden, and Miss Marple made the proper comments. If Gwenda had feared her shrewd observation of something amiss, then Gwenda was wrong. For Miss Marple showed no cognizance of anything unusual.
    Yet, strangely enough, it was Gwenda who acted in an unpredictable manner. She interrupted Miss Marple in the midst of a little anecdote about a child and a seashell to say breathlessly to Giles: 'I don't care—I'm going to tell her...'
    Miss Marple turned her head attentively. Giles started to speak, then stopped. Finally he said, 'Well, it's your funeral, Gwenda.'
    And so Gwenda poured it all out. Their call on Dr Kennedy and his subsequent call on them and what he had told them.
    'That was what you meant in London, wasn't it?' Gwenda asked breathlessly. 'You thought, then, that—that my father might be involved?'
    Miss Marple said gently, 'It occurred to me as a possibility—yes. “Helen” might very well be a young stepmother—and in a case of—er—strangling, it is so often a husband who is involved.'
    Miss Marple spoke as one who observes natural phenomena without surprise or emotion.
    'I do see why you urged us to leave it alone,' said Gwenda. 'Oh, and I wish now we had. But one can't go back.'
    'No,' said Miss Marple, 'one can't go back.'
    'And now you'd better listen to Giles. He's been making objections and suggestions.' 'All I say is,’ said Giles, 'that it doesn't fit.'
    And lucidly, clearly, he went over the points as he had previously outlined them to Gwenda.
    Then he particularized his final theory.
    'If you'll only convince Gwenda that that's the only way it could have been.'
    Miss Marple's eyes went from him to Gwenda and back again.
    'It is a perfectly reasonable hypothesis,’ she said. 'But there is always, as you yourself pointed out, Mr Reed, the possibility of X.'
    'X!' said Gwenda.
    'The unknown factor,’ said Miss Marple. 'Someone, shall we say, who hasn't appeared yet—but whose presence, behind the obvious facts, can be deduced.'
    'We're going to the Sanatorium in Norfolk where my father died,’ said Gwenda. 'Perhaps we'll find out something there.'

Sleeping Murder

Chapter 10 – A Case History
    Saltmarsh House was set pleasantly about six miles inland from the coast. It had a good train service to London from the five-miles-distant town of South Benham.
    Giles and Gwenda were shown into a large airy sitting-room with cretonne covers patterned with flowers. A very charming-looking old lady with white hair came into the room holding a glass of milk. She nodded to them and sat down near the fireplace. Her eyes rested thoughtfully on Gwenda and presently she leaned forward towards her and spoke in what was almost a whisper.
    'Is it your poor child, my dear?'
    Gwenda looked slightly taken aback. She said doubtfully: 'No—no. It isn't.'
    'Ah, I wondered.' The old lady nodded her head and sipped her milk. Then she said conversationally, 'Half past ten—that's the time. It's always at half past ten. Most remarkable.' She lowered her voice and leaned forward again.
    'Behind the fireplace,’ she breathed. 'But don't say I told you.'
    At this moment, a white uniformed maid came into the room and requested Giles and Gwenda to follow her.
    They were shown into Dr Penrose's study, and Dr Penrose rose to greet them.
    Dr Penrose, Gwenda could not help thinking, looked a little mad himself. He looked, for instance, much madder than the nice old lady in the drawing-room—but perhaps psychiatrists always looked a little mad.
    'I had your letter, and Dr Kennedy's,' said Dr Penrose. 'And I've been looking up your father's case history, Mrs Reed. I remembered his case quite well, of course, but I wanted to refresh my memory so that I should be in a position to tell you everything you wanted to know. I understand that you have only recently become aware of the facts?'
    Gwenda explained that she had been brought up in New