'Mrs Robinson!' I gasped.
'Well, there is a chance of it, anyhow,' amended Poirot. 'Also, I learn that a swarthy man, a foreigner of some kind, was inquiring about the occupants of No 4 only this morning. Therefore, mon ami, I fear that you must forswear your beauty sleep tonight, and join me in my all-night vigil in that flat below - armed with that excellent revolver of yours, bien entendu!'
'Rather,' I cried with enthusiasm. 'When shall we start?'
'The hour of midnight is both solemn and suitable, I fancy. Nothing is likely to occur before then.'
At twelve o'clock precisely, we crept cautiously into the coal-lift and lowered ourselves to the second floor. Under Poirot's manipulation, the wooden door quickly swung inwards, and we climbed into the flat. From the scullery we passed into the kitchen where we established ourselves comfortably in two chairs with the door into the hall ajar.
'Now we have but to wait,' said Poirot contentedly, closing his eyes.
To me, the waiting appeared endless. I was terrified of going to sleep. Just when it seemed to me that I had been there about eight hours - and had, as I found out afterwards, in reality been exactly one hour and twenty minutes - a faint scratching sound came to my ears. Poirot's hand touched mine. I rose, and together we moved carefully in the direction of the hall. The noise came from there.
Poirot placed his lips to my ear.
'Outside the front door. They are cutting out the lock. When I give the word, not before, fall upon him from behind and hold him fast.
Be careful, he will have a knife.'
Presently there was a rending sound, and a little circle of light appeared through the door. It was extinguished immediately and then the door was slowly opened. Poirot and I flattened ourselves against the wall. I heard a man's breathing as he passed us. Then he flashed on his torch, and as he did so, Poirot hissed in my ear:
'Allez.'
We sprang together, Poirot with a quick movement enveloped the intruder's head with a light woollen scarf whilst I pinioned his arms.
The whole affair was quick and noiseless. I twisted a dagger from his hand, and as Poirot brought down the scarf from his eyes, whilst keeping it wound tightly round his mouth, I jerked up my revolver where he could see it and understand that resistance was useless.
As he ceased to struggle Poirot put his mouth close to his ear and began to whisper rapidly. After a minute the man nodded. Then enjoining silence with a movement of the hand, Poirot led the way out of the flat and down the stairs. Our captive followed, and I brought up the rear with the revolver. When we were out in the street, Poirot turned to me.
'There is a taxi waiting just round the corner. Give me the revolver.
We shall not need it now.'
'But if this fellow tries to escape?'
Poirot smiled.
'He will not.'
I returned in a minute with the waiting taxi. The scarf had been unwound from the stranger's face, and I gave a start of surprise.
'He's not a Jap,' I ejaculated in a whisper to Poirot.
'Observation was always your strong point, Hastings! Nothing escapes you. No, the man is not a Jap. He is an Italian.'
We got into the taxi, and Poirot gave the driver an address in St John's Wood. I was by now completely fogged. I did not like to ask Poirot where we were going in front of our captive, and strove in vain to obtain some light upon the proceedings.
We alighted at the door of a small house standing back from the road. A returning wayfarer, slightly drunk, was lurching along the pavement and almost collided with Poirot, who said something sharply to him which I did not catch. All three of us went up the steps of the house. Poirot rang the bell and motioned us to stand a little aside. There was no answer and he rang again and then seized the knocker which he plied for some minutes vigorously.
A light appeared suddenly above the fanlight, and the door was opened cautiously a little way.
'What the devil do you want?' a man's voice demanded harshly.
'I want the doctor. My wife is taken ill.'
'There's no doctor here.'
The man prepared to shut the door, but Poirot thrust his foot in adroitly. He became suddenly a perfect caricature of an infuriated Frenchman.
'What you say, there is no doctor? I will have the law on you. You must come! I will stay here and ring and knock all night.'
'My dear sir - ' The door was opened again, the man, clad in a dressing-gown and slippers, stepped forward to pacify Poirot with an uneasy glance round.
'I will call the police.'
Poirot prepared to descend the steps.
'No, don't do that for Heaven's sake!' The man dashed after him.
With a neat push Poirot sent him staggering down the steps. In another minute all three of us were inside the door and it was pushed to and bolted.
'Quick - in here.' Poirot led the way into the nearest room, switching on the light as he did so. 'And you - behind the curtain.'
'Si, signor,' said the Italian and slid rapidly behind the full folds of rose-coloured velvet which draped the embrasure of the window.
Not a minute too soon. Just as he disappeared from view a woman rushed into the room. She was tall with reddish hair and held a scarlet kimono round her slender form.
'Where is my husband?' she cried, with a quick frightened glance.
'Who are you?'
Poirot stepped forward with a bow.
'It is to be hoped your husband will not suffer from a chill. I observed that he had slippers on his feet, and that his dressinggown was a warm one.'
'Who are you? What are you doing in my house?'
'It is true that none of us have the pleasure of your acquaintance, madame. It is especially to be regretted as one of our number has come specially from New York in order to meet you.'
The curtains parted and the Italian stepped out. To my horror I observed that he was brandishing my revolver, which Poirot must doubtless have put down through inadvertence in the cab.
The woman gave a piercing scream and turned to fly, but Poirot was standing in front of the closed door.
'Let me by,' she shrieked. 'He will murder me.'
'Who was it dat croaked Luigi Valdarno?' asked the Italian hoarsely, brandishing the weapon, and sweeping each one of us with it. We dared not move.
'My God, Poirot, this is awful. What shall we do?' I cried.
'You will oblige me by refraining from talking so much, Hastings. I can assure you that our friend will not shoot until I give the word.'
'You' sure o' dat, eh?' said the Italian, leering unpleasantly.
It was more than I was, but the woman turned to Poirot like a flash.
'What is it you want?'
Poirot bowed.
'I do not think it is necessary to insult Miss Elsa Hardt's intelligence by telling her.'
With a swift movement, the woman snatched up a big black velvet cat which served as a cover for the telephone.
'They are stitched in the lining of that.'
'Clever,' murmured Poirot appreciatively. He stood aside from the door. 'Good evening, madame. I will detain your friend from New York whilst you make your getaway.'