“Not today. The day before Mickey Parfitt’s body was pulled out of the river.”

The man narrowed his eyes. “Seen, like wot?”

“People coming and going, other than the ferrymen. Anyone you know behaving differently from usual. Anyone in a hurry, frightened, quarreling, running away.”

The man shook his head.

“Jeez! Yer don’t want much, do yer? All I saw were Tosh racin’ up ter Mickey on the dockside, yellin’ at ’im ter wait. Then ’e pulls a piece o’ paper out of ’is pocket an’ gives it to ’im. Mickey reads it, swears summink ’orrible, grabs a pencil from Tosh, an’ writes summink on it, then ’e gives it back to ’im. Arter that ’e calls the ferryman and tells ’im ’e’s changed ’is mind. ’E rushes away lookin’ all excited, an’ far as I know, nobody gone after ’im, nobody ’it ’im nor strangled ’im nor threw ’im in the river.”

Monk felt a sharp flicker of excitement stir inside him. “But Mickey changed his mind about where he was going?” he urged.

“I jus’ said that, yer damn fool! In’t yer listenin’?” the man snapped.

“What time was this, roughly?”

“About ’alf past ten.”

“Thank you. I’m most obliged. What is your name, if I need to speak to you again?” He nearly added, in case he needed him to testify, then thought better of it. He would send Orme for him, and allow no choice.

“ ’Orace Butterworth,” the man replied grimly. “Now get out of it. Yer frightenin’ the fish.”

Monk considered carefully how to make the best use of this delicate piece of information. Was this the message that had taken Mickey out to the boat, and then upriver toward Mortlake to meet his death? Who was it from? What had he believed he was going for? It must have been urgent, to take him back out again at that hour.

Tosh would be very unlikely to tell Monk. Nor would he tell him who the messenger was or where he’d come from. It would too easily implicate him in being party to the murder that had followed. He would simply deny it all, say that Butterworth was wrong, probably made it all up. A good lawyer would demolish the story in minutes.

He must build a chain of evidence. Who was the weakest link? ’Orrie Jones. That was where to begin.

He found ’Orrie in a boatyard patiently sanding a piece of wood. There were other men around, all sawing, planing, chiseling, carefully fitting planks, easing tongues into grooves. The ground was covered with sawdust, and it was in the air with the smell of wood and sap, and there was the constant, irregular sound of friction, banging, and someone whistling half under his breath.