‘You do not think it odd,’ asked Poirot, ‘that these strangers should come unprovided with a weapon, with gloves, with a spade, and that they should so conveniently find all these things?’
Giraud smiled in a rather superior manner. ‘Undoubtedly it is strange. Indeed, without the theory that I hold, it would be inexplicable.’
‘Aha!’ said M. Hautet. ‘An accomplice within the house!’
‘Or outside it,’ said Giraud, with a peculiar smile.
‘But someone must have admitted them. We cannot allow that, by an unparalleled piece of good fortune, they found the door ajar for them to walk in?’
‘The door was opened for them; but it could just as easily be opened from outside—by someone who possessed a key.’
‘But who would possess a key?’
Giraud shrugged his shoulders. ‘As for that, no one who possesses one is going to admit the fact if he can help it. But several people might have had one. Monsieur Jack Renauld, the son, for instance. It is true that he is on his way to South America, but he might have lost the key or had it stolen from him. Then there is the gardener—he has been here many years. One of the younger servants may have a lover. It is easy to take an impression of a key and have one cut. There are many possibilities. Then there is another person who, I should judge, is exceedingly likely to have such a thing.’
‘Who is that?’
‘Madame Daubreuil,’ said the detective.
‘Eh, eh!’ said the magistrate. ‘So you have heard about that, have you?’
‘I hear everything,’ said Giraud imperturbably.
‘There is one thing I could swear you have not heard,’ said Hautet, delighted to be able to show superior knowledge, and without more ado he retailed the story of the mysterious visitor the night before. He also touched on the cheque made out to ‘Duveen’, and finally handed Giraud the letter signed ‘Bella’.
‘All very interesting. But my theory remains unaffected.’
‘And your theory is?’
‘For the moment I prefer not to say. Remember, I am only just beginning my investigations.’
‘Tell me one thing, Monsieur Giraud’ said Poirot suddenly. ‘Your theory allows for the door being opened. It does not explain why it wasn’t open. When they departed, would it not have been natural for them to close it behind them. If a sergent had chanced to come up to the house as is sometimes done to see that all is well, they might have been discovered and overtaken almost at once.’
‘Bah! They forgot it. A mistake, I grant you.’
Then to my surprise Poirot uttered almost the same words a he had uttered to Bex the previous evening: ‘I do not agree with you. The door being left open was the result of either design or necessity, and any theory that does not admit that fact is bound to prove vain.’
We all regarded the little man with a good deal of astonishment. The confession of ignorance drawn from him over the match end had, I thought, been bound to humiliate him, but here he was self-satisfied as ever, lying down the how to Giraud without a tremor.
The detective twisted his moustache, eyeing my friend in a somewhat bantering fashion. ‘You don’t agree with me, eh? Well, what strikes you particularly about the case? Let’s hear your views.’
‘One thing presents itself to me as being significant. Tell me, Monsieur Giraud, does nothing strike you as familiar about this case? Is there nothing it reminds you of?’
‘Familiar? Reminds me of? I can’t say off-hand. I don’t think so, though.’
‘You are wrong,’ said Poirot quietly. ‘A crime almost precisely similar has been committed before.’
‘When? And where?’
‘Ah, that, unfortunately,. I cannot for the moment remember, but I shall do so. I had hoped you might be able to assist me.’
Giraud snorted incredulously. ‘There have been many affairs of masked men. I cannot remember the details of them all. The crimes all resemble each other more or less.’
‘There is such a thing as the individual touch.’ Poirot suddenly assumed his lecturing manner, and addressed us collectively. ‘I am speaking to you now of the psychology of crime. Monsieur Giraud knows quite well that each criminal has his particular method, and that the police, when called in to investigate, say, a case of burglary, can often make a shrewd guess at the offender, simply by the peculiar methods he has employed. (Japp would tell you the same, Hastings.) Man is an unoriginal animal. Unoriginal within the law in his daily respectable life, equally unoriginal outside the law. If a man commits a crime, any other crime he commits will resemble it closely. The English murderer who disposed of his wives in succession by drowning them in their baths was a case in point. Had he varied his methods, he might have escaped detection to this day. But he obeyed the common dictates of human nature, arguing that what had once succeeded would succeed again, and he paid the penalty of his lack of originality.’