“Stimulating — that’s what it was, stimulating,” added Alleyn.

“Inspector Alleyn,” said Angela furiously, “I’ll never forgive you for this — never.”

“Hist!” said Alleyn. “The very walls have ears.”

“Oh!” stormed Angela. “Oh! Oooo! Oh!”

“Murder!” said Nigel very quietly.

They walked on in silence until they came out by the river. A taxi drew up alongside them and they got in. Inspector Fox took a cardboard box from his pocket, turned delicately aside, and inserted his plates.

“Begging your pardon, miss,” he said, “but it’s pleasanter to have them.”

“And now,” said Alleyn, “just exactly what have you been up to?”

“I won’t tell you.”

“Won’t you, Miss Angela? That’s going to make it rather difficult.”

“Oh, come on, Angela,” said Nigel resignedly. “He’ll have to know. Let’s come clean.”

They came clean. The two policemen listened in silence.

“Yes,” said Alleyn when they had finished. “That’s all very interesting. It’s informative too. Let me get it straight. You say that when you quoted Miss O’Callaghan as your friend — a very dangerous trick, Miss Angela — Sage fell over backwards. Do you think he did this accidentally or deliberately? Do you think he got such a shock he overbalanced and crashed, or did you feel he used this painful ruse to distract your attention? Or were you both acting your socks off so enthusiastically that you did not notice?”

“Certainly not. At least— ”

“I think he got a shock,” said Nigel.

“Well, yes,” agreed Angela, “so do I. But he seemed more upset, oddly enough, afterwards, when he was lying there. His face went pea-green. Oh dear, he did look dreadfully funny.”

“No doubt. What did you say — did you say anything that would account for this diverting phenomenon?”

“I — no. Nigel said something. We both exclaimed, you know.”

“I grabbed hold of him and he fairly fought me off.”

“And then, you know, he got up and we asked if he was hurt and he said he was ‘quate O.K.’ and seemed to get better.”

“What was it you said, Bathgate?”

“I dunno. ‘Gosh!’ or ‘Help!’ or ‘Oh Fie!’ Something.”

“Subsequently he said that he did not altogether respond to Comrade Kakaroff’s wave of brotherly love for O’Callaghan’s murderer — that it?”

“He seemed to think that was going a bit far.”

“And yet”—Alleyn went on—“and yet I seem to remember that at the conclusion of Kakaroff’s jolly little talk, Comrade Sage leapt to his feet and yelled ‘Comrade.’ ”

“Yes — he did,” Nigel agreed, “but he may have been all carried away. He’s not a bad little tick really, I should say, once you’ve got past his frightful refinement.”

“He spoke quite decently about Miss O’Callaghan,” added Angela.

“So it appears. Did he and my girl-friend Banks have anything to say to each other?”

“Not a word.”

“Well, Fox?”

“Well, sir?”

“I suppose I visit Mr. Sage at his shop to-morrow— oh, Lard, it’s to-day, isn’t it? What’s the time?”

Inspector Fox drew his watch from the inside pocket of the threadbare coat he was wearing. He held it up in a large and filthy paw. “Just on two, I make it,” he said. “Listen.”

He lowered the window of the taxi. The lost, woebegone voice of a siren sounded out on the river. Then Big Ben, up in the cold night air, tolled two.

Inspector Fox regarded his watch with grave approval, put it away, and laid his hands on his knees.

“Longing for your bed, Fox?” asked Alleyn.

“I am for mine,” said Angela.

“Suppose we let Bathgate take the taxi on, and turn into the office for half an hour?”

“Right ho, sir.”

“Here we are.”

He tapped on the window and the taxi stopped. The two detectives got out. Their breath hung mistily on the frosty air. Alleyn spoke for a moment to the driver and then looked inside.

“Thank you so much for your help, both of you,” he said.

“I say, Alleyn, I hope you don’t think we’ve made awful mugs of ourselves?” said Nigel lugubriously.

Alleyn thought for a moment.

“It was a very spirited effort, I consider,” he said at last.

“We shall have to get you both in the Force, sir,” added Fox. His matter-of-fact voice sounded oddly remote out there in the cold.

“Ah, Inspector Fox,” said Nigel suspiciously, “I’ve heard you say that before.”

“Good night, Comrade Angela,” said Alleyn, “sleep well.”

“Good night, inspector; I don’t grudge you your joke.”

“Bless you,” answered Alleyn gently and slammed the door.

The taxi drove off. Farther along the Embankment men were hosing down the street surface. A great fan of water curved out and made all the sound there was except for the siren and the distant toot of the taxi. The two men stared at one another.

“I wonder just how much harm they’ve done,” said Alleyn.

“None at all, sir, I should say.”

“I hope you’re right. My fault if they have. Come on, let’s have a smoke.”

In Alleyn’s room they lit their pipes. Alleyn wrote at his desk for some time. Fox stared gravely at the opposite wall. They looked a queer couple with their dreadful clothes, grimy faces and blackened hands.

“She seems a very nice young lady,” Fox said presently. “Is she Mr. Bathgate’s fiancée, sir, if I may ask?”

“She is.”

“A very pleasant young couple.”

Alleyn looked at him affectionately.

“You’re a quaint old bag of nonsense.” He laid down his pen. “I don’t think, really, I took too big a risk with them. The little man was nowhere near them. You recognised him, of course?”

“Oh, yes — from the inquest. I didn’t see who it was till he passed us in the doorway, but I’d noticed him earlier in the evening. He had his back towards us.”

“Yes. I saw him, too. His clothes were good enough to shine out in that assembly. No attempt made to dress down to comrade level.”

“No,” said Fox. “Funny — that.”

“It’s altogether very rum. Passing strange. He walked straight past Sage and Nurse Banks. None of them batted an eyelash.”

“That’s so. If they are in collusion, it might be deliberate.”

“You know, Fox, I can’t think this Communist stuff is at the root of it. They’re a bogus lot, holding their little meetings, printing little pamphlets, making their spot of trouble. A nuisance from our point of view, but not the stuff that assassins are made of. Of course, given one fanatic— ” He stopped and shook his head.

“Well,” said Fox, “that’s so. They don’t amount to much. Perhaps he’s different, though. Perhaps he’s the fanatic.”

“Not that sort, I’d have thought. I’ll go and see him again. To-morrow. To-day. I rather like the bloke. We’ll have to get hold of the expert who’s doing the Kakaroff bunch and find out if he’s deep in. It’s been a field day, this. It seems an age since we sat here and waited for the report on the post-mortem. Damn. I feel we are as one about to be had. I feel we are about to give tongue and run off on a false scent. I feel we are about to put two and two together and make a mess.”

“That’s a pity,” said Fox.

“What’s the time? Half-past two. Perhaps Bathgate will be back in his own flat by now, having dropped Miss Angela, who looked tired, at her uncle’s house. I think I shall send him to bed happy.”

He dialled a number on his telephone and waited.

“Hullo, Bathgate. How much are you betting on your funny little man?”

“Roberts?” quacked Nigel’s voice clearly. “Yes, Roberts.”

“Two to one, wasn’t it? Why? What’s up?”

“Did you notice he was at the meeting to-night?”

“Roberts!”

“Yes, Roberts. Good night.” He hung up the receiver.

“Come on,” he said wearily. “Let’s put two and two together and make a mess.”