"He came along about a quarter of an hour ago," this man said quietly. "I was up here, but I told the P.C. downstairs to let him in. He looked sideways at me, and asked me when the police were going to clear out and let him have the run of his own property. He said there were letters waiting for him which he must attend to. I made difficulties and held him here. My man downstairs was instructed to ring the Yard as soon as Saint walked into the trap. He's just gone along now, sir, into the office at the end of that passage."

"Well done," said Alleyn. "Come along."

"You got a gun, sir?" asked Fox.

"No. I knew you'd have one, you old blood-thirster. Bathgate, you follow last, will you?"

They walked in silence down the long passage. Nigel was acutely aware of the odour of officialdom. Suddenly, these men whom he knew and liked had become simply policemen. "They are walking in step, I do believe," thought Nigel.

They stopped outside a steel-framed door. He could hear somebody moving about on the other side.

Alleyn knocked once, turned the handle, and walked in. The others followed, Fox with his hand in his jacket pocket.

Between their shoulders Nigel saw Jacob Saint. He had his bowler hat on, and a cigar in his mouth. He seemed to have swung round from a heap of papers on an opened desk.

"What's this?" he said.

The other officers moved apart. Alleyn walked up to him.

"Mr. Saint," he said quietly, "I have a warrant for your arrest——"

Saint made some sort of incoherent sound. Alleyn paused.

"You're mad," said Saint thickly. "I didn't do it. I wasn't there. I was in front."

"Before you go any further, you had better hear the charge."

Saint dropped into the swivel chair. He looked quickly from one man to another. His hand fumbled at the side of the desk.

"You're covered, Mr. Saint," Fox remarked suddenly. With something like a sneer, the proprietor of the Unicorn let his hands drop on to the arms of his chair.

"What's the charge?" he asked.

"You are charged with being concerned with traffic in illicit drugs. Read it out, please, Fox. I get the language wrong."

Thus urged, Inspector Fox broke instantly into a monotonous sing-song to which Saint listened closely, feasting unattractively the while on his little fingernail.

"It's infamous," he said, when Fox had stopped as abruptly as he began. "It's infamous. You—Alleyn. You'll make a laughing-stock of yourself over this. You'll lose your job."

"And that'll learn me," said Alleyn. "Come along, Mr. Saint."

Saint took his hand from his lips and let it fall to the lapel of his coat. He rose ponderously, and half turned aside.

The next second Alleyn had him by the wrist. The thick fingers held a piece of paper.

"Please, Mr. Saint," said Alleyn. "We can't have you eating paper, you know."