Holmes and I sat beside the ravaged tea-tray with our heels propped on the low table, saucers balanced on our stomachs, faces comfortably shaded from the lowering sun. The sandwich plate held only the less-identifiable creations. The biscuits were gone.

“Holmes, I take it that Inspector Jourdain was helpful?”

“Not more than he could help. The Inspector does not appear to welcome the assistance of amateurs. Particularly on a Sunday.”

“Didn’t you tell him who you were?”

“I decided that he would be even less enthusiastic over the meddling of foreign experts.”

“That will make matters difficult.”

“To be fair, the man does show signs of competence. And once he’d asserted his clear and undisputed authority over the investigation, he agreed to meet with me tomorrow—in a park, lest one of his superiors takes note—to show me the police photographs. He does not appear to be dismissing the investigation merely because Niko Cassavetes was a foreigner with dubious connections.”

“What sorts of connections?”

“Jourdain would provide no details, but he did betray an attitude towards Madame Crovetti and her son Matteo that made me suspect it lay there.”

“Madame Crovetti is a criminal? What does she do, sell fake fashion out of her shop?”

“As I say, he gave no details.”

“And yet you’ve clearly filled in some of the gaps, from the way you came swanning in stinking of beer. A pub, right? Hence, working class rather than where the bureaucrats linger.”

He stretched out his legs, looking very satisfied with himself. “We were told that Niko Cassavetes arrived in Monaco three years ago following an accident aboard a boat. We knew his manners were good, his skills more those of a personal servant than a deck hand, and he was pleasing in appearance. So yes, I went into the Monaco equivalent of a pub, near enough to the harbour for convenience, yet far enough away to be no attraction to the tourist.

“I presented myself as the chief steward on a large steam yacht due to tour the Mediterranean in the winter, scouting out local assistance. In particular, I required a man accustomed to sailing, with good manners, who spoke several languages and could drive a motorcar, and who was familiar with Riviera society. And, preferably, pleasant-looking.”

“Did any names other than his come up?”

“Surprisingly, yes. One of them was Matteo Crovetti, interestingly enough—although it was agreed that the final requirement disqualified him, unless my employer was willing to overlook the scars of smallpox on his face, and by and large it was agreed that he probably did not drive.”

“Well, most of the people here speak several languages, and Madame Crovetti would have taught her son manners. Is he a sailor?”

Ah—I’d hit the key to his self-satisfied air. He milked it by draining his cup and leaning forward to return it to the tray, then sat back again, fingers laced over his shirt-front.

“The Crovetti family are smugglers.”

“What? You mean her shop is a front?”

“Madame Crovetti, by all appearances, is nothing more than a respectable seller of expensive frocks. However, she married into a well-known family of Monégasque smugglers. All I spoke with agreed that this was in the past, that smuggling as an industry has been all but killed off. Even Crovetti senior, before he ran away with Madame Crovetti’s best shop model, had reformed, and had started a business building and hiring out luxury yachts to the winter residents. He is rumoured to be doing that same thing now in the Caribbean. But when I asked if young Matteo might be available for hire, there was a certain degree of uncomfortable laughter, and I was urged to try one of the other names on offer.”

“That confirms the impression we had from Madame Crovetti, that there was something embarrassing about her son’s absence.”

“It would also explain why Inspector Jourdain suspects that Niko Cassavetes was supplying more than artists’ sketch-books and American fireworks displays. However, I was more interested in Jourdain’s fervent insistence that, once I have satisfied myself with the photos, I have nothing further to do with the matter.”

“So why show them to you at all?”

“I may have given him the impression that I mistrusted the skills of the Monaco police department when it came to investigations. Also, that if I was convinced that they did know their jobs, I would be satisfied with providing legal defence to the lady accused of the young man’s murder, and promptly withdraw my nose from their business.”

“His is a common enough attitude, when it comes to the meddling of professional amateurs like you.”

“True. Except that the degree of urgency points to some deeper concern. As if he has been ordered to distract me from the shark in the waters.”

I looked at him over my cup. “Are we talking about Basil Zaharoff? Or does Monaco have a whole collection of world-rank criminals?”

“He’s not the only scoundrel here, though he is the biggest.”

The shadow from The Rock was creeping across the harbour, taking the bright gleam from yachts, skiffs, and the white sea-plane. “Holmes, I do understand the compromises people make when it comes to money, but in a place this small, where the Prince can stand at his window over there and survey the entire populace? I’d have thought there would be a bit more…distaste. If for no reason other than snobbery.”

“Neutrality has its ethical costs. Being unable to choose a side and take a stand may be good for business, but hard on the self-esteem.”

“And I suppose that this Prince does spend his time outside the country, like all the others,” I mused. “However, surely that can’t be all you came up with? You’ve been gone all day.”

“Being rebuffed by the police took less than an hour, and drinking establishments tend not to fill until the afternoon. In between, I had time to hire a car and be outside of the prison when Mrs Hudson came out.”

“Who picked her up?”

“A driver—who took her directly to the house of Lillie Langtry. And in the next two hours, the only person to go in and out was the companion, Mathilde, who was gone for forty minutes and returned with a string bag of vegetables and a small box from the local patisserie.”

“So they don’t plan on holding a large party tonight.”

“If they do, the guests have little appetite for cake.”

“Good. So if they’re busy eating pastry, perhaps I could offer you a spot of housebreaking?”

That cheered him right up. First, I reviewed my day, skipping over the cleaning and that disturbing lingerie to focus on Mrs Hudson’s furnishings, the contents of her wardrobe, and finally, the gold-and-garnet earrings.

“The fact that she did not wear them in Sussex does not mean those are new,” he noted.

“Although the box they are in is. And I’m fairly certain that she hasn’t had them for long.”

“Why?”

This was somewhat embarrassing, having so recently protested Holmes’ lack of faith in our housekeeper. “You remember how I told you that some years ago, on a visit home from University, I had a poke through Mrs Hudson’s things?”

“Where you found a derringer, and her son’s birth certificate.”

“That’s right. She did have some nice pieces in her jewellery box, but these earrings were not among them. And the placement on her dressing table, by themselves, rather than in her little jewellery box, would suggest that they are recent acquisitions.”

“Perhaps she bought them in Paris, to go with the clothing she purchased.”

“They weren’t the kind of things she’d have bought herself.”

“Too expensive?”

“Too…unnecessary.” Did I know her taste, I wondered? I hardly knew her any more—but I felt that the Mrs Hudson I knew, in any of her guises, would prefer solid beauty to showiness. “The evening dresses she bought in Paris are on the edge of ostentatious. Still appropriate for an older woman, yet aiming to make an impression. If she’d bought a pair of earrings to go with them, she’d have chosen something more extravagant.”

“So, a personal gift?”

“I’d say so.”

“I see. And are the earrings related to your proposal of housebreaking?”

“Only indirectly. She also had a pair of old shoes with a kind of grey mud on the soles.”

“I do not yet know Monaco well enough to identify its soils.”

“Perhaps I can help. After we’d finished cleaning, I talked Madame Crovetti into taking me next door, into that converted warehouse. Her son Matteo lives there, or does when he’s in the country. Two years ago he let his back rooms to Niko Cassavetes. Who has a pair of Wellingtons with a similar grey soil on them.”

“Aha.” The sound was praise indeed.

“And you know that massively expensive bottle of wine we drank the other night?”

“The Château de—”

I cut into his loving recitation of its pedigree. “That one, yes. The one with the grey sort of dust on it.”

He raised an eyebrow. “The same?”

“Certainly very similar to the naked eye.”

“Any idea where?” Because clearly I did.

“I might have.”

“Hence, the housebreaking.”

“But not until Madame Crovetti has gone to bed.”

“We have time for dinner, then.”

“Though perhaps not another entire bottle of expensive wine.”

“My friend the sommelier will be disappointed.”

He was. But it did mean that we were both stone-cold sober when we slipped away from the Hermitage, dressed in dark clothing and with various tools in our pockets. We kept to the lesser streets, and found no lights on in Madame Crovetti’s trio of buildings. The nearest street-lamp was far enough away to make picking the lock more a matter of touch than sight. Once inside the musty space, I switched on my electric torch, leaving my hand loosely across the lens in case our keen-eyed police constable happened by.

I let the muffled beam play over the furniture, then checked the other rooms as well, but the only creatures I saw had multiple legs. We did find a back door—one that was not fastened shut. It opened onto a narrow delivery lane behind the other two houses, but we explored no further, lest Madame Crovetti be lying awake.

I led Holmes back through Matteo Crovetti’s rooms to the crude dividing wall with the well-kept door, where I paused to run my light over the creased wallpaper.

“This divider is more recent than the building. It looks to me as if they decided to chop a storage shed or workshop into two sides with a rough wooden wall, then at some point, covered over the cracks with flowered paper. You can see how well that works.” I opened the door, running the unshielded beam over the room behind, but it, too, was empty. Once the door was closed, I switched on the electrical lamp near the settee and reached behind it to pull aside the bedcover-tapestries. As I’d anticipated, they were there to block draughts around a set of wide delivery doors. “This would have been the access for carts and such, making deliveries around the back of the Crovetti house.” The doors had been sealed shut, although twenty minutes with screw-driver would free them.

I let the tapestry fall, and took Holmes to the bedroom with the sloping back wall. In Niko’s makeshift wardrobe, I lifted some garments off their hooks to reveal the wall behind. “Does that look like a door to you?” I asked.

It did not, in fact, resemble a door. It would have looked like a bodged-together wall over a raw cliff-face—except for the greyish soil, ground into the floor-boards.

I held the torch while Holmes dropped to his knees in front of the suspicious patch of wall. His sensitive fingers ran up and down the roughly painted surface, concentrating on an area that looked marginally more grimy…

It clicked.

I expected a cubby-hole, a place to store small, but valuable possessions. I watched Holmes lean inside the cleverly disguised doorway—then he rose and stepped through it.