Agatha Christie - Murder in Mesopotamia

He paused.

‘Yes?’ said Dr Leidner.

‘In the third place,’ said Poirot slowly, ‘I can, I think, appreciate devotion when I see it. I believe, Dr Leidner, that your love for your wife was the ruling passion of your life. It is so, is it not?’

Dr Leidner answered quite simply: ‘Yes.’

Poirot nodded.

‘Therefore,’ he said, ‘we can proceed.’

‘Hear, hear, let’s get down to it,’ said Dr Reilly with some impatience.

Poirot gave him a reproving glance.

‘My friend, do not be impatient. In a case like this everything must be approached with order and method. In fact, that is my rule in every case. Having disposed of certain possibilities, we now approach a very important point. It is vital that, as you say – all the cards should be on the table – there must be nothing kept back.’

‘Quite so,’ said Dr Reilly.

‘That is why I demand the whole truth,’ went on Poirot.

Dr Leidner looked at him in surprise.

‘I assure you, M. Poirot, that I have kept nothing back. I have told you everything that I know. There have been no reserves.’

‘Tout de meme, you have not told me everything.’

‘Yes, indeed. I cannot think of any detail that has escaped me.’

He looked quite distressed.

Poirot shook his head gently.

‘No,’ he said. ‘You have not told me, for instance, why you installed Nurse Leatheran in the house.’

Dr Leidner looked completely bewildered.

‘But I have explained that. It is obvious. My wife’s nervousness – her fears…’

Poirot leaned forward. Slowly and emphatically he wagged a finger up and down.

‘No, no, no. There is something there that is not clear. Your wife is in danger, yes – she is threatened with death, yes. You send – not for the police – not for a private detective even – but for a nurse! It does not make the sense, that!’

‘I – I–’ Dr Leidner stopped. The colour rose in his cheeks. ‘I thought–’ He came to a dead stop.

‘Now we are coming to it,’ Poirot encouraged him. ‘You thought – what?’

Dr Leidner remained silent. He looked harassed and unwilling.

‘See you,’ Poirot’s tone became winning and appealing, ‘it all rings what you have told me, except for that. Why a nurse? There is an answer – yes. In fact, there can be only one answer. You did not believe yourself in your wife’s danger.’

And then with a cry Dr Leidner broke down.

‘God help me,’ he groaned. ‘I didn’t. I didn’t.’

Poirot watched him with the kind of attention a cat gives a mouse-hole – ready to pounce when the mouse shows itself.

‘What did you think then?’ he asked.

‘I don’t know. I don’t know…’

‘But you do know. You know perfectly. Perhaps I can help you – with a guess. Did you, Dr Leidner, suspect that these letters were all written by your wife herself? ’

There wasn’t any need for him to answer. The truth of Poirot’s guess was only too apparent. The horrified hand he held up, as though begging for mercy, told its own tale.

I drew a deep breath. So I had been right in my half-formed guess! I recalled the curious tone in which Dr Leidner had asked me what I thought of it all. I nodded my head slowly and thoughtfully, and suddenly awoke to the fact that M. Poirot’s eyes were on me.

‘Did you think the same, nurse?’

‘The idea did cross my mind,’ I said truthfully.

‘For what reason?’

I explained the similarity of the handwriting on the letter that Mr Coleman had shown me.

Poirot turned to Dr Leidner.

‘Had you, too, noticed that similarity?’

Dr Leidner bowed his head.

‘Yes, I did. The writing was small and cramped – not big and generous like Louise’s, but several of the letters were formed the same way. I will show you.’

From an inner breast pocket he took out some letters and finally selected a sheet from one, which he handed to Poirot. It was part of a letter written to him by his wife. Poirot compared it carefully with the anonymous letters.

‘Yes,’ he murmured. ‘Yes. There are several similarities – a curious way of forming the letters, a distinctivee. I am not a handwriting expert – I cannot pronounce definitely (and for that matter, I have never found two handwriting experts who agree on any point whatsoever) – but one can at least say this – the similarity between the two handwritings is very marked. It seems highly probable that they were all written by the same person. But it is not certain. We must take all contingencies into mind.’

He leaned back in his chair and said thoughtfully: ‘There are three possibilities. First, the similarity of the handwriting is pure coincidence. Second, that these threatening letters were written by Mrs Leidner herself for some obscure reason. Third, that they were written by someone who deliberately copied her handwriting. Why? There seems no sense in it. One of these three possibilities must be the correct one.’

He reflected for a minute or two and then, turning to Dr Leidner, he asked, with a resumal of his brisk manner: ‘When the possibility that Mrs Leidner herself was the author of these letters first struck you, what theory did you form?’

Dr Leidner shook his head.

‘I put the idea out of my head as quickly as possible. I felt it was monstrous.’

‘Did you search for no explanation?’

‘Well,’ he hesitated. ‘I wondered if worrying and brooding over the past had perhaps affected my wife’s brain slightly. I thought she might possibly have written those letters to herself without being conscious of having done so. That is possible, isn’t it?’ he added, turning to Dr Reilly.

Dr Reilly pursed up his lips.

‘The human brain is capable of almost anything,’ he replied vaguely.

But he shot a lightning glance at Poirot, and as if in obedience to it, the latter abandoned the subject.

‘The letters are an interesting point,’ he said. ‘But we must concentrate on the case as a whole. There are, as I see it, three possible solutions.’

‘Three?’

‘Yes. Solution one: the simplest. Your wife’s first husband is still alive. He first threatens her and then proceeds to carry out his threats. If we accept this solution, our problem is to discover how he got in or out without being seen.

‘Solution two: Mrs Leidner, for reasons of her own (reasons probably more easily understood by a medical man than a layman), writes herself threatening letters. The gas business is staged by her (remember, it was she who roused you by telling you she smelt gas). But, if Mrs Leidner wrote herself the letters, she cannot be in danger from the supposed writer. We must, therefore, look elsewhere for the murderer. We must look, in fact, amongst the members of your staff. Yes,’ in answer to a murmur of protest from Dr Leidner, ‘that is the only logical conclusion. To satisfy a private grudge one of them killed her. That person, I may say, was probably aware of the letters – or was at any rate aware that Mrs Leidner feared or was pretending to fear someone. That fact, in the murderer’s opinion, rendered the murder quite safe for him. He felt sure it would be put down to a mysterious outsider – the writer of the threatening letters.

‘A variant of this solution is that the murderer actually wrote the letters himself, being aware of Mrs Leidner’s past history. But in that case it is not quite clear why the criminal should have copied Mrs Leidner’s own handwriting since, as far as we can see, it would be more to his or her advantage that they should appear to be written by an outsider.

‘The third solution is the most interesting to my mind. I suggest that the letters are genuine. They are written by Mrs Leidner’s first husband (or his younger brother), who is actually one of the expedition staff.’