Mallett cut him short with a “That’ll do!” The story might be true or not. He had sufficient experience of the terror that certain classes feel towards anything connected with the police to be prepared to credit it. But it was of little moment whether the man was lying or speaking the truth, now that he had provided the essential evidence.

“You talk about ‘Anglo-Dutch’ as if he was a person,” he said. “Did only one man use these offices, then?”

“At the start there was two or three used to come in and out, when they was moving in. After that there was only just the one. I never found out ’is name—that’s why I called ’im Anglo-Dutch.”

“Did he come regularly?”

“Most days—not every day. ’E’d come in the morning, ten o’clock or thereabouts, and leave in the evening. I never seed ’im go out to lunch, even. I used to wonder what ’e did there all day by ’isself. ’E never ’ad no callers.”

Mallett produced a photograph from his pocket.

“Did he look anything like this?” he asked.

The caretaker peered at it doubtfully.

“I’m a bit short-sighted,” he confessed. “I wouldn’t like to swear that’s the same man, not on oath, I wouldn’t.”

“But is it like him?”

“Oh, yes, it’s like ’im all right. The same sort of man, you might say. But it’s no good asking me to swear——”

“I’m not,” said Mallett curtly, and strode away.

But for all the sharpness of his words, his heart was singing. For the photograph he had shown to the caretaker was a copy of the police photograph of Mr. Colin James, and the umbrella under his arm was the umbrella of Lionel Ballantine.