‘I have learned that Menier was in Tunis preparing the way for a theft from the Holy Fathers when your telegram arrived. Father Lavigny, who was in ill-health, was forced to refuse, but Menier managed to get hold of the telegram and substitute one of acceptance. He was quite safe in doing so. Even if the monks should read in some paper (in itself an unlikely thing) that Father Lavigny was in Iraq they would only think that the newspapers had got hold of a half-truth as so often happens.
‘Menier and his accomplice arrived. The latter is seen when he is reconnoitring the antika-room from outside. The plan is for Father Lavigny to take wax impressions. Ali then makes clever duplicates. There are always certain collectors who are willing to pay a good price for genuine antiques and will ask no embarrassing questions. Father Lavigny will effect the substitution of the fake for the genuine article – preferably at night.
‘And that is doubtless what he was doing when Mrs Leidner heard him and gave the alarm. What can he do? He hurriedly makes up a story of having seen a light in the antika-room.
‘That “went down”, as you say, very well. But Mrs Leidner was no fool. She may have remembered the trace of wax she had noticed and then put two and two together. And if she did, what will she do then? Would it not be dans son caractere to do nothing at once, but enjoy herself by letting hints slip to the discomfiture of Father Lavigny? She will let him see that she suspects – but not that she knows. It is, perhaps, a dangerous game, but she enjoys a dangerous game.
‘And perhaps she plays that game too long. Father Lavigny sees the truth, and strikes before she realizes what he means to do.
‘Father Lavigny is Raoul Menier – a thief. Is he also – a murderer?’
Poirot paced the room. He took out a handkerchief, wiped his forehead and went on: ‘That was my position this morning. There were eight distinct possibilities and I did not know which of these possibilities was the right one. I still did not know who was the murderer.
‘But murder is a habit. The man or woman who kills once will kill again.
‘And by the second murder, the murderer was delivered into my hands.
‘All along it was ever present in the back of my mind that some one of these people might have knowledge that they had kept back – knowledge incriminating the murderer.
‘If so, that person would be in danger.
‘My solicitude was mainly on account of Nurse Leatheran. She had an energetic personality and a brisk inquisitive mind. I was terrified of her finding out more than it was safe for her to know.
‘As you all know, a second murder did take place. But the victim was not Nurse Leatheran – it was Miss Johnson.
‘I like to think that I should have reached the correct solution anyway by pure reasoning, but it is certain that Miss Johnson’s murder helped me to it much quicker.
‘To begin with, one suspect was eliminated – Miss Johnson herself – for I did not for a moment entertain the theory of suicide.
‘Let us examine now the facts of this second murder.
‘Fact One: On Sunday evening Nurse Leatheran finds Miss Johnson in tears, and that same evening Miss Johnson burns a fragment of a letter which nurse believes to be in the same handwriting as that of the anonymous letters.
‘Fact Two: The evening before her death Miss Johnson is found by Nurse Leatheran standing on the roof in a state that nurse describes as one of incredulous horror. When nurse questions her she says, “I’ve seen how someone could come in from outside – and no one would ever guess.” She won’t say any more. Father Lavigny is crossing the courtyard and Mr Reiter is at the door of the photographic-room.
‘Fact Three: Miss Johnson is found dying. The only words she can manage to articulate are “the window – the window–”
‘Those are the facts, and these are the problems with which we are faced:
‘What is the truth of the letters?
‘What did Miss Johnson see from the roof?
‘What did she mean by “the window – the window”?
‘Eh bien, let us take the second problem first as the easiest of solution. I went up with Nurse Leatheran and I stood where Miss Johnson had stood. From there she could see the courtyard and the archway and the north side of the building and two members of the staff. Had her words anything to do with either Mr Reiter or Father Lavigny?
‘Almost at once a possible explanation leaped to my brain. If a stranger came in from outside he could only do so in disguise. And there was only one person whose general appearance lent itself to such an impersonation. Father Lavigny! With a sun helmet, sun glasses, black beard and a monk’s long woollen robe, a stranger could pass in without the servants realising that a stranger had entered.
‘Was that Miss Johnson’s meaning? Or had she gone further? Did she realize that Father Lavigny’s whole personality was a disguise? That he was someone other than he pretended to be?
‘Knowing what I did know about Father Lavigny, I was inclined to call the mystery solved. Raoul Menier was the murderer. He had killed Mrs Leidner to silence her before she could give him away. Now another person lets him see that she has penetrated his secret. She, too, must be removed.
‘And so everything is explained! The second murder. Father Lavigny’s flight – minus robe and beard. (He and his friend are doubtless careering through Syria with excellent passports as two commercial travellers.) His action in placing the blood-stained quern under Miss Johnson’s bed.
‘As I say, I was almost satisfied – but not quite. For the perfect solution must explain everything – and this does not do so.
‘It does not explain, for instance, why Miss Johnson should say “the window”, as she was dying. It does not explain her fit of weeping over the letter. It does not explain her mental attitude on the roof – her incredulous horror and her refusal to tell Nurse Leatheran what it was that she now suspected or knew.
‘It was a solution that fitted the outer facts, but it did not satisfy the psychological requirements.
‘And then, as I stood on the roof, going over in my mind those three points: the letters, the roof, the window, I saw – just as Miss Johnson had seen!
‘And this time what I saw explained everything!’
Chapter 28. Journey’s End
Poirot looked round. Every eye was now fixed upon him. There had been a certain relaxation – a slackening of tension. Now the tension suddenly returned.
There was something coming…something…
Poirot’s voice, quiet and unimpassioned, went on: ‘The letters, the roof, “the window”…Yes, everything was explained – everything fell into place.
‘I said just now that three men had alibis for the time of the crime. Two of those alibis I have shown to be worthless. I saw now my great – my amazing mistake. The third alibi was worthless too. Not only could Dr Leidner have committed the murder – but I was convinced that he had committed it.’
There was a silence, a bewildered, uncomprehending silence. Dr Leidner said nothing. He seemed lost in his far-away world still. David Emmott, however, stirred uneasily and spoke.
‘I don’t know what you mean to imply, M. Poirot. I told you that Dr Leidner never left the roof until at least a quarter to three. That is the absolute truth. I swear it solemnly. I am not lying. And it would have been quite impossible for him to have done so without my seeing him.’
Poirot nodded.
‘Oh, I believe you. Dr Leidner did not leave the roof. That is an undisputed fact. But what I saw – and what Miss Johnson had seen – was that Dr Leidner could murder his wife from the roof without leaving it.’