Rutledge had walked the dog the third time, glimpsing the sweep working on his brushes as if something about them troubled him. The nanny was now unrecognizable as a shopgirl flirting with a young army private. Another man was arguing with a friend, and Rutledge caught part of what Sergeant Gibson was saying so earnestly-his views on the Labor Party and what the government ought to do about people out of work.

We’ve got the same number of actors-Rutledge thought, bringing the dog to heel again after allowing it to explore among the trees along the edge of the grass. It doesn’t vary.

No murderer worth his salt would walk into such a carefully managed trap.

And then Phipps was there again, carrying his umbrella, a folded copy of The Times under his arm. He looked like a retired solicitor, his nose red from the cold, his attention fixed on the distant traffic, just barely heard here in the park.

It was a waste of time, Hamish was saying.

Rutledge answered, “One of the murder victims sold pipes in a shop. The other was a conductor on an omnibus. What did they have in common, that made them a target?”

“It wilna’ be how they earned their living.”

“True enough.” Rutledge let the dog walk ahead to the base of one of the great trees that had given the park its name. “This was a place where men dueled, once. A long time ago.”

“Oh, aye? But to use a garrote properly, you must come from behind. No’ face-to-face. It’s no’ an honorable encounter!”

“A woman, then?”

Hamish answered, thoughtful. “There’s no woman, else yon Chief Inspector would ha’ had her name by now fra’ someone eager to turn her in for prostitution.”

“A gaming debt?”

“A warning,” Hamish countered.

And that, thought Rutledge, was very likely the case. A warning to stay in line-or die.

But for what? From whom?