From across the street, Hawker heard the faint jingle as a muscular clerical gentleman emerged, hunched in the rain opening his umbrella, and strode off carrying a large, oblong package under his arm.

It was short of noon, but lamps were lit inside the shop, paying blackmail to the mucky gloom of the day. He and Pax had pulled back to the line of shop fronts, just to give the carriages a challenge if they wanted to soak somebody. They stood in the doorway of an antique dealer across the street from Voyages. Nothing much else happened, except everybody got wet.

Inside Justine’s shop, two customers stood at the counter and examined every possible aspect of some small metal instrument, passing it back and forth between them. The shop clerk, a Negro, tall and thin as an ebony cane, advised and discussed and sometimes pointed. This went on.

The clerk was calling himself Mr. Thompson now. He’d used a half dozen other names when he worked for the French.

Pax said, “Somehow I never expected Justine DuMotier to end up a shopkeeper on Exeter Street.”

“A surprise for all of us.”

“Everybody buys here. Good business. Doyle watched her for months when she first set up to see if it was legitimate.”

“I know.”

“I figured you knew everything you wanted to know.”

Three years ago, when Napoleon fell, Justine DuMotier disappeared from the sight of man. He’d looked for her everywhere, worried as hell. Paris was full of occupying armies. Petty, rancorous men tracked down Napoleon’s followers to pay back old scores. The new French government was thinning the ranks of the Police Secrète, not being frugal with the bullets.

It had been months before the Service spotted her in London. More months, before he got back to England himself.

He remembered. He’d landed in Dover, ridden up from the coast in a night and a day, dropped his kit at Meeks Street, and walked straight here. To her.

It had been late afternoon of the day, and foggy. The shop was lit up inside, the way it was now. He’d stood . . . He’d stood almost exactly at this spot and watched her at the counter of her shop, fifty feet away. She’d unrolled a big map and was showing a gentleman customer some river on it, or a sea route. Something that involved leaning over close and tracing a line with her finger.

He’d stayed in the shadow, watching. Didn’t go into the shop. The war was over, but it didn’t make any difference. The last words she’d said to him dug a chasm he hadn’t dared to cross.

“What do you think that is?” Pax said, meaning the instrument everybody was so fascinated with, inside.

“Sextant maybe. A small one. And that’s the case for it.”

“We don’t buy from her,” Pax said. “The Military Intelligence boys do. The navy officers. The Ethnological Club. The Service goes to Barnes instead.”

“That’s tactful of us.”

“We like to think so.”

Voyages designed and sold gear for travel to the far corners of the globe. Now that the war was over, Englishmen were pouring out of dull old England, headed to Egypt, South America, India, and every port in the Orient. Voyages was the first stop. They knew what you needed. They’d buy it for you or make it, and pack it up neat. The expeditions Justine supplied never ended up hiking through the monsoon in wool underdrawers. Her guns didn’t misfire during some sticky dispute with Afghani bandits. That clerical gentleman with the umbrella wouldn’t run out of soap and ipecac while he was bringing enlightenment to the Maori.

Voyages also did a roaring trade in luncheon hampers with nested teacups and a little brazier for under the teapot, suitable for picnics when exploring the far reaches of Hampstead Heath with an elderly aunt.

“She makes a good living,” Pax said. “Half of England’s traipsing around the remote and uncomfortable.”

“Getting bit by snakes and skewered by the outraged local inhabitants.”

“It’s the English way.” Pax refolded his arms. “Those two don’t look like they’re leaving anytime soon, do they?”

The black man placed another enigmatic metal instrument on the counter. A theodolite. Everybody took a look at it.

“Not soon,” he said.

Pax shifted an inch, edging out of the path of a persistent drip coming down from the roof. “Speaking professionally, if I wanted to kill Justine—just a simple death—I’d shoot her in the shop.”

“Speaking professionally, that would be a wise choice.” He kept his voice level. Rage had been simmering away inside him for a good long while. He’d keep it there, boiling away in his gut, till he needed it. “They waited till she came to me. They must have known she’d come.”

“Then they know her. They can predict what she’ll do.”

“A small, elite group. The man who did the stabbing was watching her and waiting. Probably from . . .” He looked up and behind him, got rain in his eyes. “One of these windows.”

“I’ll bring the boys. We’ll start asking questions, up and down the street.”

“The pub over there has a front table with a view of the shop.” In the last two years, he’d sat there sometimes, pursuing a lengthy acquaintance with a glass of gin, knowing Justine would walk by and he’d get to see her. There could not be anything in the world more pitiable than a man afraid to face a woman. Unless the woman was Justine DuMotier. “Ask in the shops if anyone’s been looking in that direction. But it’ll turn out to be a room upstairs.”

“One of those.” Pax glanced across houses, assessing likelihoods. They’d avoided ambushes in the war years, knowing where shots were likely to come from. Sometimes, they’d been the men doing the shooting.

That was the dark secret of the assassin’s trade. It’s not that hard. A stab in the alley. The pull of a trigger. People were so damn fragile—ten breaths or two minutes bleeding separated life and death.

Justine had turned out to be hard to kill. A nasty surprise for somebody.

Pax said, “Looks like they’re winding up.”

The pair in Justine’s shop finally agreed that the first mechanical device, whatever it was, suited their purpose. The black man set it carefully in a box, left the room to go into the back of the shop, and came out with brown paper. There was more talking, all round, while he wrapped the box. Everybody nodded and shook hands. Then the two men left the shop and walked down Exeter Street in close conversation.

He said, “And we have the place to ourselves.”

They crossed the street. Pax, beside him, watched the right hand. He watched the left. He didn’t feel eyes on him right at the moment. But then, he’d been wrong about that on some notable occasions in the past.

At the door he pulled his hat off and shook the rain off. He set it back on his head so he’d have both hands free.

The bell jangled as they walked in. The black man, Mr. Thompson, looked up from a book, open flat on the counter. His eyes slid across Pax. He saw Hawker and knew him.