‘You have an answer to everything,’ said Dr Leidner.
I was thinking hard. Right from the beginning I had thought Mr Coleman’s manner rather more like a P.G. Wodehouse book than like a real live young man. Had he really been playing a part all the time?
Poirot was writing in a little book.
‘Let us proceed with order and method,’ he said. ‘On the first count we have two names. Father Lavigny and Mr Mercado. On the second we have Coleman, Emmott and Reiter.
‘Now let us pass to the opposite aspect of the matter—means and opportunity. Who amongst the expedition had the means and the opportunity of committing the crime? Carey was on the dig, Coleman was in Hassanieh, you yourself were on the roof. That leaves us Father Lavigny, Mr Mercado, Mrs Mercado, David Emmott, Carl Reiter, Miss Johnson and Nurse Leatheran.’
‘Oh!’ I exclaimed, and I bounded in my chair.
Mr Poirot looked at me with twinkling eyes.
‘Yes, I’m afraid, ma soeur, that you have got to be included. It would have been quite easy for you to have gone along and killed Mrs Leidner while the courtyard was empty. You have plenty of muscle and strength, and she would have been quite unsuspicious until the moment the blow was struck.’
I was so upset that I couldn’t get a word out. Dr Reilly, I noticed, was looking highly amused.
‘Interesting case of a nurse who murdered her patients one by one,’ he murmured.
Such a look as I gave him!
Dr Leidner’s mind had been running on a different tack.
‘Not Emmott, M. Poirot,’ he objected. ‘You can’t include him. He was on the roof with me, remember, during that ten minutes.’
‘Nevertheless we cannot exclude him. He could have come down, gone straight to Mrs Leidner’s room, killed her, and then called the boy back. Or he might have killed her on one of the occasions when he had sent the boy up to you.’
Dr Leidner shook his head, murmuring: ‘What a nightmare! It’s all so—fantastic.’
To my surprise Poirot agreed.
‘Yes, that’s true. This is a fantastic crime. One does not often come across them. Usually murder is very sordid—very simple. But this is unusual murder…I suspect, Dr Leidner, that your wife was an unusual woman.’
He had hit the nail on the head with such accuracy that I jumped.
‘Is that true, nurse?’ he asked.
Dr Leidner said quietly: ‘Tell him what Louise was like, nurse. You are unprejudiced.’
I spoke quite frankly.
‘She was very lovely,’ I said. ‘You couldn’t help admiring her and wanting to do things for her. I’ve never met anyone like her before.’
‘Thank you,’ said Dr Leidner and smiled at me.
‘That is valuable testimony coming from an outsider,’ said Poirot politely. ‘Well, let us proceed. Under the heading of means and opportunity we have seven names. Nurse Leatheran, Miss Johnson, Mrs Mercado, Mr Mercado, Mr Reiter, Mr Emmott and Father Lavigny.’
Once more he cleared his throat. I’ve always noticed that foreigners can make the oddest noises.
‘Let us for the moment assume that our third theory is correct. That is that the murderer is Frederick or William Bosner, and that Frederick or William Bosner is a member of the expedition staff. By comparing both lists we can narrow down our suspects on this count to four. Father Lavigny, Mr Mercado, Carl Reiter and David Emmott.’
‘Father Lavigny is out of the question,’ said Dr Leidner with decision. ‘He is one of the Pères Blancs in Carthage.’
‘And his beard’s quite real,’ I put in.
‘Ma soeur,’ said Poirot, ‘a murderer of the first class never wears a false beard!’
‘How do you know the murderer is of the first class?’ I asked rebelliously.
‘Because if he were not, the whole truth would be plain to me at this instant—and it is not.’
That’s pure conceit, I thought to myself.
‘Anyway,’ I said, reverting to the beard, ‘it must have taken quite a time to grow.’
‘That is a practical observation,’ said Poirot.
Dr Leidner said irritably: ‘But it’s ridiculous—quite ridiculous. Both he and Mercado are well-known men. They’ve been known for years.’
Poirot turned to him.