“Pardon?” said Gibson.

“A traitor in their ranks. A snout.”

“Oh. Ah.”

“They must at the very least have suspected it. I’d give a hell of a lot to know what happened at that meeting while you and I, Fox, sat outside in the Mews. Who did they suspect? Why? What did they plan? To have another go at the President? It seems unlikely that Sheridan-Gomez would have given up. Did any of them get wind of Sanskrit’s visit to the Embassy last night? And who the devil was the shadow we saw sprinting round the alley-corner?”

“Come on, Mr. Alleyn. What’s the theory? Who do you reckon?”

“Oh, I’ll tell you that, Br’er Fox,” Alleyn said. And did.

“And if either of you lot,” he ended, “so much as mumbles the word ‘conjecture’ I’ll put you both on dab for improper conduct.”

“It boils down to this, then,” said Fox. “They may be contemplating a second attempt on the President or they may be setting their sights on the snout whoever they reckon him to be, or they may be split on their line of action. Or,” he added as an afterthought, “they may have decided to call it a day, wind up the Klu-Klux-Fish and fade out in all directions.”

“How true. With which thought we, too, part company. We must be all-ways away, Br’er Fox. Some to kill cankers in the musk-rose buds—”

“What’s all that about?” Gibson asked glumly.

“Quotations,” Fox said.

“Yes, Fred,” said Allen, “and you can go and catch a red-hipped bumble-bee on the lip of a thistle while Fox and I war with reremice for their leathern wings.”

“Who said all the bumph anyway?”

“Fairies. We’ll keep in touch. Come on, Fox.”

They returned to their own anonymous car and were driven to the Capricorns. Here a discreet prowl brought them into touch with one of Gibson’s men, a plain-clothes sergeant, who had quite a lot to say for himself. The fishy brotherhood had not been idle. Over the last half-hour the Cockburn-Montforts had been glimpsed through their drawing-room window engaged in drinking and — or so it seemed — quarrelling in a desultory way between libations. Chubb had been followed, by a plain-clothes sergeant carrying artist’s impedimenta, to a chemist’s shop in Baronsgate, where he handed in a prescription and sat down, presumably waiting for it to be made up. Seeing him settle there, the sergeant returned to Capricorn Mews, where, having an aptitude in that direction, he followed a well-worn routine by sitting on a canvas stool and making a pencil sketch of the pig-pottery. He had quite a collection of sketches at home, some finished and prettily tinted and aquarelles, others of a rudimentary kind, having been cut short by an arrest or by an obligation to shift the area of investigation. For these occasions he wore jeans, a dirty jacket, and an excellent wig of the Little Lord Fauntleroy type. His name was Sergeant Jacks.

Mr. Sheridan, the Cockburn-Montforts and the Sanskrits had not appeared.

Fox parked the car in its overnight position under the plane trees in Capricorn Square, from where he could keep observation on No. 1, the Walk, and Alleyn took a stroll down the Mews. He paused behind the gifted sergeant and, after the manner of the idle snooper, watched him tinker with a tricky bit of perspective. He wondered what opulent magic Troy at that moment might be weaving, over in Chelsea.

“Anything doing?” he asked.

“Premises shut up, sir. But there’s movement. In the back of the shop. There’s a bit of a gap in the curtains and you can just get a squint. Not to see anything really. Nobody been in or out of the flat entrance.”

“I’ll be within range. No. 1, Capricorn Walk. Give me a shout if there’s anything. You could nip into that entry to call me up.”

“Yes, sir.”

Two youths from the garage strolled along and stared.

Alleyn said: “I wouldn’t have the patience, myself. Don’t put me in it,” he added. These were the remarks by bystanders that Troy said were most frequently heard. “Is it for sale?” he asked.

“Er,” said the disconcerted sergeant.

“I might come back and have another look,” Alleyn remarked, and left the two youths to gape.

He pulled his hat over his left eye, walked very quickly indeed across the end of Capricorn Place and on into the Walk. He had a word with Fox in the car under the plane trees and then crossed the street to No. 1, where Mr. Whipplestone, who had seen him coming, let him in.

“Sam,” Alleyn said. “Chubb did go to the chemist.”

“I’m extremely glad to hear it.”

“But it doesn’t necessarily mean he won’t call at the piggery, you know.”

“You think not?”

“If he suffers from migraine the stresses of the past forty-eight hours might well have brought it on.”

“I suppose so.”

“Is his wife in?”

“Yes,” said Mr. Whipplestone, looking extremely apprehensive.

“I want to speak to her.”

“Do you? That’s — that’s rather disturbing.”

“I’m sorry, Sam. It can’t be helped, I’m afraid.”

“Are you going to press for information about her husband?”

“Probably.”

“How very — distasteful.”

“Police work is, at times, precisely that.”

“I know. I’ve often wondered how you can.”

“Have you?”

“You strike me, always, as an exceptionally fastidious man.”

“I’m sorry to disenchant you.”

“And I’m sorry to have been tactless.”

“Sam,” Alleyn said gently, “one of the differences between police work and that of other and grander services is that we do our own dirty washing instead of farming it out at two or three removes.”

Mr. Whipplestone turned pink. “I deserved that,” he said.

“No, you didn’t. It was pompous and out of place.”

Lucy Lockett, who had been washing herself with the zeal of an occupational therapist, made one of her ambiguous remarks, placed her forepaw on Alleyn’s knee, and leapt neatly into his lap.

“Now then, baggage,” Alleyn said, scratching her head, “that sort of stuff never got a girl anywhere.”

“You don’t know,” Mr. Whipplestone said, “how flattered you ought to feel. The demonstration is unique.”

Alleyn handed his cat to him and stood up. “I’ll get it over,” he said. “Is she upstairs, do you know?”

“I think so.”

“It won’t take long, I hope.”

“If I — if I can help in any way—?”

“I’ll let you know,” said Alleyn.

He climbed the stairs and tapped on the door. When Mrs. Chubb opened it and saw him, she reacted precisely as she had on his former visit. There she stood, speechless with her fingers on her lips. When he asked to come in she moved aside with the predictable air of terrified reluctance. He went in and there was the enlarged photograph of the fresh-faced girl. The medallion, even, was, as before, missing from its place. He wondered if Chubb was wearing it.

“Mrs. Chubb,” he said, “I’m not going to keep you long and I hope I’m not going to frighten you. Yes, please, do sit down.”

Just as she did last time, she dropped into her chair and stared at him. He drew his up and leant forward.

“Since I saw you yesterday,” he said, “we have learnt a great deal more about the catastrophe at the Embassy and about the people closely and remotely concerned in it. I’m going to tell you what I believe to be your husband’s part.”

She moved her lips as if to say: “He never—” but was voiceless.

“All I want you to do is listen and then tell me if I’m right, partly right or wholly mistaken. I can’t force you to answer, as I expect you know, but I very much hope that you will.”

He waited for a moment and then said: “Well. Here it is. I believe that your husband, being a member of the group we talked about yesterday, agreed to act with them in an attack upon the President of Ng’ombwana. I think he agreed because of his hatred of blacks and of Ng’ombwanans in particular.” Alleyn looked for a moment at the smiling photograph. “It’s a hatred born of tragedy,” he said, “and it has rankled and deepened, I daresay, during the last five years.