There was a sudden stampede. Willis saw the angry face of Dickie as he lurched past him and heard him swearing. Somebody caught his hand. He ran up the rose-alley, panting. Something caught his foot, and he tripped and fell. His companion abandoned him, and ran on, hooting. He sat up, found his head enveloped in his hood and struggled to release himself.

A hand touched his shoulder.

“Come on, Mr. Willis,” said a mocking voice in his ear, “Mr. Bredon says I am to escort you home.”

He succeeded in dragging the black cloth from his head and scrambled to his feet.

Beside him stood Pamela Dean. She had taken off her mask, and her eyes were alight with mischief.

Lord Peter Wimsey had paid a call upon Chief-Inspector Parker of Scotland Yard, who was his brother-in-law.

He occupied a large and comfortable arm-chair in the Chief-Inspectors Bloomsbury flat. Opposite him, curled upon the chesterfield, was his sister, Lady Mary Parker, industriously knitting an infant’s vest. On the window-seat, hugging his knees and smoking a pipe, was Mr. Parker himself. On a convenient table stood a couple of decanters and a soda siphon. On the hearthrug was a large tabby cat. The scene was almost ostentatiously peaceful and domestic.

“So you have become one of the world’s workers, Peter,” said Lady Mary.

“Yes; I’m pulling down four solid quid a week. Amazin’ sensation. First time I’ve ever earned a cent. Every week when I get my pay-envelope, I glow with honest pride.”

Lady Mary smiled, and glanced at her husband, who grinned cheerfully back. The difficulties which are apt to arise when a poor man marries a rich wife had, in their case, been amicably settled by an ingenious arrangement, under which all Lady Mary’s money had been handed over to her brothers in trust for little Parkers to come, the trustee having the further duty of doling out each quarter to the wife a sum precisely equal to the earnings of the husband during that period. Thus a seemly balance was maintained between the two principals; and the trifling anomaly that Chief-Inspector Parker was actually a mere pauper in comparison with small Charles Peter and still smaller Mary Lucasta, now peacefully asleep in their cots on the floor above, disturbed nobody one whit. It pleased Mary to have the management of their moderate combined income, and incidentally did her a great deal of good. She now patronized her wealthy brother with all the superiority which the worker feels over the man who merely possesses money.

“But what is the case all about, exactly?” demanded Parker.

“Blest if I know,” admitted Wimsey, frankly. “I got hauled into it through Freddy Arbuthnot’s wife-Rachel Levy that was, you know. She knows old Pym, and he met her at dinner somewhere and told her about this letter that was worrying him, and she said, Why not get somebody in to investigate it, and he said, Who? So she said she knew somebody-not mentioning my name, you see-and he said would she ask him to buzz along, so I buzzed and there I am.”

“Your narrative style,” said Parker, “though racy, is a little elliptical. Could you not begin at the beginning and go on until you come to the end, and then, if you are able to, stop?”

“I’ll try,” said his lordship, “but I always find the stopping part of the business so difficult. Well, look! On a Monday afternoon-the 25th of May, to be particular, a young man, Victor Dean by name, employed as a copy-writer in the firm of Pym’s Publicity, Ltd., Advertising Agents, fell down an iron spiral staircase on their premises, situated in the upper part of Southampton Row, and died immediately of injuries received, to wit: one broken neck, one cracked skull, one broken leg and minor cuts and contusions, various. The time of this disaster was, as nearly as can be ascertained, 3.30 in the afternoon.”

“Hum!” said Parker. “Pretty extensive injuries for a fall of that kind.”

“So I thought, before I saw the staircase. To proceed. On the day after this occurrence, the sister of deceased sends to Mr. Pym a fragment of a half-finished letter which she has found on her brother’s desk. It warns him that there is something of a fishy nature going on in the office. The letter is dated about ten days previous to the death, and appears to have been laid aside as though the writer wanted to think over the wording a bit more carefully. Very good. Now, Mr. Pym is a man of rigid morality-except, of course, as regards his profession, whose essence is to tell plausible lies for money-”

“How about truth in advertising?”

“Of course, there is some truth in advertising. There’s yeast in bread, but you can’t make bread with yeast alone. Truth in advertising,” announced Lord Peter sententiously, “is like leaven, which a woman hid in three measures of meal. It provides a suitable quantity of gas, with which to blow out a mass of crude misrepresentation into a form that the public can swallow. Which incidentally brings me to the delicate and important distinction between the words ‘with’ and ‘from.’ Suppose you are advertising lemonade, or, not to be invidious, we will say perry. If you say ‘Our perry is made from fresh-plucked pears only,’ then it’s got to be made from pears only, or the statement is actionable; if you just say it is made ‘from pears,’ without the ‘only,’ the betting is that it is probably made chiefly of pears; but if you say, ‘made with pears,’ you generally mean that you use a peck of pears to a ton of turnips, and the law cannot touch you-such are the niceties of our English tongue.”

“Make a note, Mary, next time you go shopping, and buy nothing that is not ‘from, only.’ Proceed, Peter-and let us have a little less of your English tongue.”

“Yes. Well, here is a young man who starts to write a warning letter. Before he can complete it, he falls downstairs and is killed. Is that, or is it not, a darned suspicious circumstance?”

“So suspicious that it is probably the purest coincidence. But since you have a fancy for melodrama, we will allow it to be suspicious. Who saw him die?”

“I, said the fly. Meaning one Mr. Atkins and one Mrs. Crump, who saw the fall from below, and one Mr. Prout who saw it from above. All their evidence is interesting. Mr. Prout says that the staircase was well-lit, and that deceased was not going extra fast, while the others say that he fell all of a heap, forwards, clutching The Times Atlas in so fierce a grip that it could afterwards hardly be prised from his fingers. What does that suggest to you?”

“Only that the death was instantaneous, which it would be if one broke one’s neck.”

“I know. But look here! You are going downstairs and your foot slips. What happens? Do you crumple forwards and dive down head first? Or do you sit down suddenly on your tail and do the rest of the journey that way?”

“It depends. If it was actually a slip, I should probably come down on my tail. But if I tripped, I should very likely dive forwards. You can’t tell, without knowing just how it happened.”

“All right. You always have an answer. Well, now-do you clutch what you’re carrying with a deathly grip-or do you chuck it, and try to save yourself by grabbing hold of the banisters?”

Mr. Parker paused. “I should probably grab,” he said, slowly, “unless I was carrying a tray full of crockery, or anything. And even then… I don’t know. Perhaps it’s an instinct to hold on to what one’s got. But equally it’s an instinct to try and save one’s self. I don’t know. All this arguing about what you and I would do and what the reasonable man would do is very unsatisfactory.”

Wimsey groaned. “Put it this way, doubting Thomas. If the death-grip was due to instantaneous rigor, he must have been dead so quickly that he couldn’t think of saving himself. Now, there are two possible causes of death-the broken neck, which he must have got when he pitched on his head at the bottom, and the crack on the temple, which is attributed to his hitting his skull on one of the knobs on the banisters. Now, falling down a staircase isn’t like falling off a roof-you do it in instalments, and have time to think about it. If he killed himself by hitting the banisters, he must have fallen first and hit himself afterwards. The same thing applies, with still more force, to his breaking his neck. Why, when he felt himself going, didn’t he drop everything and break his fall?”