One must see with eyes of the mind; one must employ the little cells of grey! Know, then, that tonight and on the night of the Victory Ball, you saw not six figures but five! Seel'

The lights went out again. A figure bounded in front of the screen - Pierrotl

'Who is that?' demanded Poirot. 'Is it Pierrot?' 'Yes,' we all cried.

'Look again['

With a swift movement the man divested himself of his loose Pierrot garb. There in the limelight stood glittering Harlequinl At the same moment there was a cry and an overturned chair.

'Curse you,' snarled Davidson's voice. 'Curse youl How did you gue?'

When came the clink of handcuffs and Japp's calm official voice.

'I arrest you, Christopher Davidson - charge of murdering

Viscount Cronshaw - anything you say used in evidence against you.'

It was a quarter of an hour later. A recherch little supper had appeared; and Poirot, beaming all over his face, was dispensing hospitality and answering our eager questions.

'It was all very simple. The circumstances in which the green pompon was found suggested at once that it had been torn from the costume of the murderer. I dismissed Pierrette from my mind (since it takes considerable strength to drive a table-knife home) and fixed upon Pierrot as the criminal. But Pierrot left the ball nearly two hours before the murder was committed. So he must either have returned to the ball later to kill Lord Cronshaw, or eh bien, he must have killed him before he left! Wras that impossible?

Who had seen Lord Cronshaw after supper that evening? Only Mrs Davidson, whose statement, I suspected, was a deliberate fabrication uttered with the object of accounting for the missing pompon, which, of course, she cut from her own dress to replace the one missing on her husband's costume. But then, Harlequin, who was seen in the box at one-thirty, must have been an impersonation.

For a moment, earlier, I had considered the possibility of Mr Beltane being the guilty party. But with his elaborate costume, it was clearly impossible that he could have doubled the roles of Punchinello and Harlequin. On the other hand, to David-son, a young man of about the same height as the murdered man and an actor by profession, the thing was simplicity itself.

'But one thing worried me. Surely a doctor could not fail to perceive the difference between a man who had been dead two hours and one who had been dead ten minutes! Eh amp;n, the doctor did perceive it! But he was not taken to the body and asked "How long has this man been dead?" On the contrary, he was informed that the man had been seen alive ten minutes ago, and so he merely commented at the inquest on the abnormal stiffening of the limbs for which he was quite unable to accountl 'All was now marching famously for my theory. Davidson had killed Lord Cronshaw immediately after supper, when., as you remember, he was seen to draw him back into the supper-room.

Then he departed with Miss Courtenay, left her at the door of her flat (instead of going in and trying to pacify her as he affirmed) and returned post-haste to the Colossus - but as Harlequin, not Pierrot - a simple transformation effected by removing his outer costume.'

The uncle of the dead man leaned forward, his eyes perplexed.

'But if so, he must have come to the ball prepared to kill his victim. What earthly motive could he have had? The motive, that's what I can't get.'

'Ah! There we come to the second tragedy - that of Miss Courtenay. There was one simple point which everyone over-looked.

Miss Courtenay died of cocaine poisoning - but her supply of the drug was in the enamel box which was found on Lord Cronshaw's body. Where, then, did she obtain the dose which killed her? Only one person could have supplied her with it -Davidson.

And that explains everything. It accounts for her friendship with the Davidsons and her demand that Davidson should escort her home. Lord Cronshaw, who was almost fanatic-ally opposed to drug-taking, discovered that she was addicted to cocaine, and suspected that Davidson supplied her with it.

Davidson doubtless denied this, but Lord Cronshaw determined to get the truth from Miss Courtenay at the ball. He could forgive the wretched girl, but he would certainly have no mercy on the man who made a living by trafficking in drugs. Exposure and ruin confronted Davidson. He went to the ball determined that

Cronshaw's silence must be obtained at any cost.'

'Was Coco's death an accident, then?'

'I suspect that it was an accident cleverly engineered by Davidson. She was furiously angry with Cronshaw, first for his reproaches, and secondly for taking her cocaine from her. Davidson supplied her with more, and probably suggested her augmenting the dose as a defiance to "old Cronch'T

'One other thing,' I said. 'The recess and the curtain? How did you know about them?'

'Why, rnon ami, that was the most simple of all. Waiters had been in and out of that little room, so, obviously, the body could

not have been lying where it was found on the floor. There must be some place in the room where it could be hidden. I deduced a curtain and a recess behind it. Davidson dragged the body there, and later, after drawing attention to himself in the box, he dragged it out again before finally leaving the Hall. It was one of his best moves. He is a clever fellow?

But in Poirot's green eyes I read unmistakably the unspoken remark: 'But not quite so clever as Hercule Poirotl'

At the time that I was sharing rooms with my friend Hercule Poirot, it was my custom to read aloud to him the headlines in the morning newspaper, the Daily Blare.

The Daily Blare was a paper that made the most of any opportunity for sensationalism. Robberies and murders did not lurk obscurely in its back pages. Instead they hit you in the eye in large type on the front page.

ABSCONDING BANK CLERK DISAPPEARS WITH FI17TY THOUSAND POUNDS' WORTH OF NEGOTIABLE SECURITIES, I read.

HUSBAND PUTS HIS HEAD IN GAS-OVEN. UNHAPPY HOME LI17.

MISSING TYPIST. PRETTY OIRL O17 TWENTY-ONE. WHEI IS EDNA FIELD?

'There you are, Poirot, plenty to choose from. An absconding bank clerk, a mysterious suicide, a missing typist - which will you have?' My friend was in a placid mood. He quietly shook his head.

'I am not greatly attracted to any of them, mon ant/. Today I feel inclined for the life of ease. It would have to be a very interesting problem to tempt me from my chair. See you, I have affairs of importance of my own to attend to.' 'Such as?' 'My wardrobe, Hastings. If I mistake not, there is on my new grey suit the spot of grease- only the unique spot, but it is sufficient to trouble me. Then there is my winter overcoat - I must lay him aside in the powder of Keatings. And I think - yes, I think - the moment is ripe for the trimmings of my moustaches - and afterwards I must apply the pomade.' 'Well,' I said, strolling to the window, 'I doubt if you'll be able to carry out this delirious programme. That was a ring at the bell.

You have a client.'

'Unless the affair is one of national importance, I touch it not,' declared Poirot with dignity.

A moment later our privacy was invaded by a stout red-faced lady who panted audibly as a result of her rapid ascent of the stairs.

'You're M. Poirot?' she demanded, as she sank into a chair.

'I am Hercule Poirot, yes, madame.'

'You're not a bit like what I thought you'd be,' said the lady, eyeing him with some disfavour. 'Did you pay for the bit in the paper saying what a clever detective you were, or did they put it in themselves?'

'Madamel' said Poirot, drawing himself up.

'I'm sorry, I'm sure, but you know what these papers are nowadays. You begin reading a nice article "What a bride said to her plain unmarried friend", and it's all about a simple thing you buy at the chemist's and shampoo your hair with. Nothing but puff. But no offence taken, I hope? I'll tell you what I want you to do for me. I want you to find my cook.'