The plan was that if no one robbed him on the way down to Greenwich, he was to meet with one of the other policemen who was dressed as a passenger and show him the carving, as if intending to sell it to him. The policeman would pretend to decline and Monk would return to Westminster. He refused even to imagine the possibility of the thieves taking it and not being caught. On the other hand, if they were arrested too soon, then the whole operation was abortive. The police would have the thief-the fingers of the crime-but not the brain or the heart.

A man bumped against him, apologized, and moved on.

Monk's hands went to his pocket. The carving was still there.

It happened again, and again. He was so nervous his fingers were stiff and trembling.

Butterworth bumped into him and apologized, using the password to let him know that he had been robbed. Why was the carving not gone? Without the theft they would not need to find the Fat Man.

They were past the Surrey Docks and heading down the Limehouse Reach.

Ten minutes later Monk's pocket was empty, and he had not even felt it. Panic broke over him in a wave, the sweat hot and then cold on his skin. He had no idea who had taken it, not even whether it was man or woman. He spun around. Where was Butterworth?

"Thin man, mustache, sad face like a rat," Constable Jones said almost at his elbow. "Over there, by the way up to the deck."

Monk found himself gasping with relief, barely able to draw enough air into his lungs. Should he say he knew who had taken the statue? The lie died on his lips. Jones would see in his reaction that he had not. "Thank you," he said instead. "He's the one we have to watch, never mind the others."

Butterworth was almost six feet from the man with the mustache. He was pretending to look for something in his coat pocket, but his eyes were on the man. He had seen, too. He and Jones were good, quicker than Monk.

The boat reached the Dog and Duck Stairs, and the man with the carving got off. Monk, Jones, and Butterworth got off behind him, as did half a dozen others.

The man walked down the quay back towards the Greenland Dock. It was dark, and there was a smell of rain in the wind. Here and there the streetlamps were lit. It was in some ways the most difficult time to keep anyone in sight. The shadows were deceptive; you thought you saw someone, and suddenly you didn't. There were pools of light, and long stretches of gloom. The sound and movement and shifting reflections of water were everywhere.