Mr Chubb was standing by the window in Purbright’s office. The light fell on silvery hair, sleek but cut short. His face, half averted in contemplation of buildings opposite, was of that paradoxical solemnity so often characteristic of the man who has never really worried about anything in his life.
“This so-called Syndicate,” the chief constable continued, “apparently employs assassins to further its interests. Yes, I know it sounds rather like medieval Italy, but there you are: these things do go on and we have to take a realistic view.
“Anyway, the long and short of the matter is that our worthy opposite numbers in New York have warned me officially that just such an assassin has been ordered to come to England—to Flaxborough, in fact: they were quite specific.”
Chubb paused.
“And with what object, sir?”
“Presumably,” replied the chief constable, looking at once judicious and regretful, “in order to attempt the murder of someone or other.”
“A local person?”
“Ah, well, that we do not know, do we, Mr Purbright. I would prefer to think not, but our main concern must be to see that the would-be assassin is prevented from doing any damage to anybody, whoever they are.
“This”—Mr Chubb produced a teleprinted sheet—“is a copy of the letter which the New York police received yesterday.”
Purbright rose but Chubb, crossing from the window, motioned him back into his chair and put the paper before him. The inspector, who was several inches taller than the chief constable, had long since learned to accept without false protest Mr Chubb’s preference for standing.
“So they really do use expressions like these,” the inspector said when he had finished reading.
“What we should term thieves’ argot, I suppose,” said Mr Chubb, knowledgeably.
“ ‘Contract’ is pithy, sir. A lawyer’s word. Significant, perhaps, of the ever narrowing division between them and their clients.”
Chubb’s regard of his inspector chilled momentarily but made no comment.
“I don’t need to ask if our New York friends take this seriously,” Purbright said. “Obviously they wouldn’t have passed it on otherwise. And the probability of its not being a hoax is strengthened by the mention of a specific place. An obscure and unimportant place. In the New York context, I mean, of course,” he hastily qualified. “It’s a circumstantial detail that stands out rather impressively from the Spillanery.”
“Oh, I don’t think the genuineness of the warning is at issue, Mr Purbright.” Chubb had no idea what “Spillanery” might be but would as soon have asked as put on a pair of jeans. “Our job is to act upon it as a matter of urgency.”
Purbright nodded earnestly. “Of course, sir.” He reached for a note pad. “You will have in mind some main lines of action?
“Yes, but I would not wish to prejudice your own ideas at this stage, Mr Purbright. If you will tell me what they are, we may possibly save ourselves a certain amount of duplication.”
The inspector drew a line down the middle of the top sheet of the pad. “You will have seen straight away that our problem can be divided into two parts,” he said. “So I propose to adopt the same approach as must already have occurred to you.”
“Ah,” said the chief constable, in the manner of one commending perspicacity.
“It is, in fact, an X and Y problem, sir. Where X is the journeying criminal, the assassin or potential assassin, and Y the intended victim. If we could establish the identity of either one of these two unknowns, our task would be very much easier. You are thinking”—Purbright gave Chubb a wry smile—“of quadratic equations, naturally. Not at all a bad analogy.”
The chief constable shrugged modestly and looked down to see if Purbright had written anything yet. One or two notes had appeared on the left of the dividing line.
“All we know about this man X,” Purbright went on, “is that he is probably an American citizen—probably, but not certainly; that he is a member of an organisation of some kind—again probably, although I suppose there may be freelance murderers available; and that he is likely to have chosen as inconspicuous a way of travelling as possible—as an ordinary tourist, in fact.
“Twenty or thirty years ago, such a man could not have come into Flaxborough without being noticed by at least a dozen people who would have started a chain reaction of gossip. Nowadays, I doubt if there are fewer than ten American visitors in the town at any one time between June and September.”
If Mr Chubb found this estimate surprising, he did not challenge it.
“It did occur to me,” he said, “that one of your fellows ought to check the visitors’ books at all the hotels. Twice a day, perhaps; there can’t be very many.”
“Three, actually, sir. There has been a good deal of shrinkage in that area.”
“That should simplify things, then.”
“Yes, sir. At least we shall be able to discount the families and concentrate upon anyone who registers on his own. An assassin taking his wife and children along on his expense account doesn’t sound very possible.”
“Or very ethical,” added the chief constable, who liked occasionally to lend support to Mrs Chubb’s loyal contention that her husband had a dry sense of humour.
“There is always the slight hope,” said the inspector, “that the man X has a bad enough record, or else sufficiently spectacular criminal associations, to justify his being picked up on the way here, preferably before he can get on a plane.”
“The immigration people are extremely diligent, I understand.”
“No doubt, sir. But sheer weight of numbers can defeat the most stringent precautions. I still have a sort of Rider Haggard sense of wonder when I read of all those grenades and submachine guns that passengers manage to lug aboard aeroplanes.
“Anyway, so much for the X factor. Unless, of course”—Purbright looked up inquiringly—“you have a further line you’d like me to pursue?”
Mr Chubb examined the sleeve of his light grey worsted jacket. “It all sounds rather pessimistic, Mr Purbright. A criminal who cannot be identified can scarcely be apprehended.”
“Very well put, sir. Now I can see how you arrived at the analogy of algebra. Let me just trace the argument for my own satisfaction—oh, and please pull me up if I go wrong.
“As we well know, quadratic equations are simply statements of the relationships that certain unknowns bear to one another and, either singly or in combination, to known factors of the same kind. The solution is obtained by manipulating these relationships until each unknown is isolated by cancelling the others out. Do I follow you, sir?”
Mr Chubb, wooden-faced, gave an almost imperceptible nod. He stole a glance at Sergeant Love who was doing something with papers on a table, but Love seemed totally absorbed in his task.