We had scarcely reached the first floor when the Nylands’ door opened and Mrs. Nyland came out. She looked older than she had appeared to be in the midnight street but young enough and with the physique, a kind of high-toned stringiness, of a woman who has been an athlete or a dancer. She wore a voluminous T-shirt and shorts which showed long dark-brown well-muscled legs.

“Oh, excuse me!” There’s a certain kind of middle-aged woman, the county sort of whom I had seen plenty in Suffolk, who never say “excuse me” without prefacing it with “Oh.” The tone is authoritative and the last word rises to a high interrogatory note. “Oh, excuse me!” Hers was a perfect exponent of the art of it. “But where exactly do you think you’re going?”

It had all happened very quickly. We had never thought of any excuse or reason for going up to 4E, though we should have done after bumping into Sean Francis. Silver came out with the truth. There was really no choice.

“Some friends of ours live on the top floor.”

“Are you quite sure of that?”

The door behind her had swung wide open. The hall was unlike anywhere else in the building and quite unlike 15 Russia Road. The carpet was black and the furniture white. A huge black-and-white abstract in a stainless-steel frame hung on the wall facing us. Silently, walking on sandaled feet, the man we had seen get out of the taxi came out into the hall and stood in front of it. The woman turned her head and spoke to him in a rather softer tone.

“Darling, I caught these people going to the top floor. They say friends of theirs live up there. Rather odd, don’t you think?”

Nyland came nearer. “Not squatters, are you?”

“Look,” Silver said, “let us just get this stuff up there, will you? Then you can come up and check.”

He told me later he was expecting to have called their bluff. If he invited them up to 4E, in the nature of things they wouldn’t come, they’d be satisfied. But they weren’t. Nyland, who was a very tall skinny man, the Clint Eastwood type, looked even more suspicious than his wife. He said he’d follow us up now.

Those were a nerve-racking forty-five seconds. With me going first and Silver behind me and Nyland behind him, I thought we had a chance. Luckily, Andrew happened to be just behind the door when I rang our code. I mouthed, “Hide Jason.”