Ackroyd stared blankly at me as though he hardly understood.

I began to realize that there must be something very I'm sure Miss Russell knows far more about high society than I do. I didn't attempt to argue with her.

'Just tell me this, doctor,' said Miss Russell. 'Suppose you are really a slave of the drug habit, is there any cure?' One cannot answer a question like that off-hand. I gave her a short lecture on the subject, and she listened with close attention. I still suspected her of seeking information about Mrs Ferrars.

'Now, veronal, for instance -' I proceeded.

But, strangely enough, she didn't seem interested in veronal. Instead she changed the subject, and asked me if it was true that there were certain poisons so rare as to baffle detection.

'Ah!' I said. 'You've been reading detective stories.' She admitted that she had.

'The essence of a detective story,' I said, 'is to have a rare poison - if possible something from South America, that nobody has ever heard of- something that one obscure tribe of savages use to poison their arrows with. Death is instantaneous, and Western science is powerless to detect it.

Is that the kind of thing you mean?' 'Yes. Is there really such a thing?' I shook my head regretfully.

'I'm afraid there isn't. There's curare, of course.' I told her a good deal about curare, but she seemed to have lost interest once more. She asked me if I had any in my poison cupboard, and when I replied in the negative I fancy I fell in her estimation.

She said she must be getting back, and I saw her out at the surgery door just as the luncheon gong went.

I should never have suspected Miss Russell of a fondness for detective stories. It pleases me very much to think of her stepping out of the housekeeper's room to rebuke a delinquent housemaid, and then returning to a comfortable perusal of The Mystery of the Seventh Death, or something of the kind.

I told Caroline at lunch that I should be dining at Fernly. She expressed no objection - on the contrary.

'Excellent,' she said. 'You'll hear all about it. By the way, what is the trouble with Ralph?' 'With Ralph?' I said, surprised; 'there isn't any.' 'Then why is he staying at the Three Boars instead of at Fernly Park?' I did not for a minute question Caroline's statement that Ralph Paton was staying at the local inn. That Caroline said so was enough for me.

'Ackroyd told me he was in London,' I said. In the surprise of the moment I departed from my valuable rule of never parting with information.

'Oh!' said Caroline. I could see her nose twitching as she worked on this.

'He arrived at the Three Boars yesterday morning,' she said. 'And he's still there. Last night he was out with a girl.' That did not surprise me in the least. Ralph, I should say, is out with a girl most nights of his life. But I did rather wonder that he chose to indulge in the pastime in King's Abbot instead of in the gay Metropolis.

'One of the barmaids?' I asked.

'No. That's just it. He went out to meet her. I don't know…who she is.' (Bitter for Caroline to have to admit such a thing.) 'But I can guess,' continued my indefatigable sister.

I waited patiently.

'His cousin.' 'Flora Ackroyd?' I exclaimed in surprise.

Flora Ackroyd is, of course, no relation whatever really to Ralph Paton but Ralph has been looked upon for so long as if practically Ackroyd's own son, that cousinship is taken for granted.

'Flora Ackroyd,' said my sister.

'But why not go to Fernly if he wanted to see her?' 'Secretly engaged,' said Caroline, with immense enjoyment.

'Old Ackroyd won't hear of it, and they have to meet this way.' I saw a good many flaws in Caroline's theory, but I forebore to point them out to her. An innocent remark about our new neighbour created a diversion.

The house next door, The Larches, has recently been taken by a stranger. To Caroline's extreme annoyance, she has not been able to find out anything about him, except that he is a foreigner. The Intelligence Corps has proved a broken reed. Presumably the man has milk and vegetables and joints of meat and occasional whitings just like everybody else, but none of the people who make it their business to supply these things seem to have acquired any information.

His name, apparently, is Mr Porrott ~ a name which conveys an odd feeling of unreality. The one thing we do know about him is that he is interested in the growing of vegetable marrows.

But that is certainly not the sort of information that Caroline is after. She wants to know where he comes from, what he does, whether he is married, what his wife was, or is, like, whether he has children, what his mother's maiden name was - and so on. Somebody very like Caroline must have invented the questions on passports, I think.

'My dear Caroline,' I said. 'There's no doubt at all about what the man's profession has been. He's a retired hairdresser. Look at that moustache of his.' Caroline dissented. She said that if the man was a hairdresser, he would have wavy hair - not straight. All hairdressers did.

I cited several hairdressers personally known to me who had straight hair, but Caroline refused to be convinced.

'I can't make him out at all,' she said in an aggrieved voice. 'I borrowed some garden tools the other day, and he was most polite, but I couldn't get anything out of him. I asked him point blank at last whether he was a Frenchman, and he said he wasn't - and, somehow, I didn't like to ask him any more.' I began to be more interested in our mysterious neighbour. A man who is capable of shutting up Caroline and sending her, like the Queen of Sheba, empty away, must be something of a personality.

'I believe,' said Caroline, 'that he's got one of those new vacuum cleaners ' I saw a meditated loan and the opportunity of further questioning gleaming from her eye. I saw the chance to escape into the garden. I am rather fond of gardening. I was busily exterminating dandelion roots when a shout of warning sounded from close by and a heavy body whizzed by my ears and fell at my feet with a repellent squelch. It was a vegetable marrow!

I looked up angrily. Over the wall, to my left, there appeared a face. An egg-shaped head, partially covered with suspiciously black hair, two immense moustaches, and a pair of watchful eyes. It was our mysterious neighbour, Mr Porrott.

He broke at once into fluent apologies. 'I demand of you a thousand pardons, monsieur. I am without defence. For some months now I cultivate the marrows. This morning suddenly I enrage myself with these marrows. I send them to promenade themselves - alas! not only mentally but physically. I seize the biggest. I hurl him over the wall. Monsieur, I am ashamed. I prostrate myself.' Before such profuse apologies, my anger was forced to melt. After all, the wretched vegetable hadn't hit me. But I sincerely hoped that throwing large vegetables over walls was not our new friend's hobby. Such a habit could hardly endear him to us as a neighbour.

The strange little man seemed to read my thoughts.

'Ah! no,' he exclaimed. 'Do not disquiet yourself. It is not with me a habit. But you can figure to yourself, monsieur, that a man may work towards a certain object, he may labour and toil to attain a certain kind of leisure and occupation, and then find that, after all, he yearns for the old busy days, and the old occupations that he thought himself so glad to leave?' 'Yes,' I said slowly. 'I fancy that that is a common enough occurrence. I myself am perhaps an instance. A year ago I came into a legacy - enough to enable me to realize a dream. I have always wanted to travel, to see the world. Well, that was a year ago, as I said, and - I am still here.' My little neighbour nodded.