Gabrielle started to exchange a “boys!” look with Laura. Recalling that Laura was the enemy, she abruptly pulled her chin back into her collar.

“Come close by me,” Laura said, pulling the little boy to her side as they started across the river. Below, the boatmen plied their trade, ferrying passengers along the Seine. The narrow crafts looked like water bugs as they darted along between the banks of the river. “Or you’ll need fins instead of wings.”

“I don’t want fins.”

“You will if you fall in the Seine.” When Pierre-André looked intrigued, she added hastily, “I wouldn’t advise it. That water is icy cold.”

“How cold?”

“Too cold for a butterfly to survive—or a little boy.” She reached a protective hand out to Gabrielle as a wagon trundled past them, but Gabrielle jerked away. She hunched her shoulders up beneath her coat and walked faster, doing everything she could to distance herself from the new governess and her brother. To their right, the buttresses of Notre-Dame soared in a feat of medieval engineering, commanding the skyline, while beyond it, one could just make out the long façade of the Louvre palace. In the sunshine, they glowed golden, the windows sparkling like diamonds. Laura saw Gabrielle’s eyes widen at the sight, then carefully drop to her feet, determined not to show she was impressed.

Laura let Gabrielle have her little act of defiance. It was dreadful to be nine. It wasn’t an age one would want to live over: too old to be cooed over, too young to be treated as an equal, stuck betwixt and between, and happy with no one.

Laura and Pierre-André followed behind Gabrielle, responding to the little boy’s chatter by rote as he kept up a running commentary on the boats, the sky, the other inhabitants of the bridge, and what it might be like to be a butterfly with fins.

“There are butterfly fish,” said Laura absently. “But I believe they live in the tropics, not here. We can find you a book with pictures of them when we get to the bookseller.”

Gabrielle twisted around. “There are booksellers,” she said, pointing at the stalls by the side of the river. “Why can’t we buy books there?”

“Those aren’t the right kind of books,” replied Laura imperturbably. “We’re going to a proper shop.”

The Rue Serpente, they had told her. What could be more innocent than a trip to the bookshop? Governesses taught. Teaching required books. Even a nasty, suspicious, French Ministry of Police-trained mind couldn’t find any fault with that.

Laura summoned Gabrielle closer as they crossed over into the Left Bank, home of students and stews. There was a sour reek of spilled wine about the streets as they set off down a winding alley towards the Rue Serpente, but the bookshop itself looked respectable enough, with narrow, dark windows piled high with books. Despite herself, Gabrielle’s eyes brightened at the display.

Ha! thought Laura. Got you.

A little bell tinkled as Laura pushed open the door. The shop gave the impression of being even smaller and more cluttered than it actually was, with books piled on tables and racks and stacked in uneven towers propped against the walls. A small coal brazier burned in one corner of the shop, puffing out smoke and warmth. In summer, the windows would be open to the street, with books spilling out onto tables outside, but now the windows were shuttered tight against the January chill, making the room feel like a bibliophilic Ali Baba’s cave, dark and crowded with treasure.

The smell of leather, binding glue, paper, and coal dust brought back powerful memories of other bookshops. Laura paused just inside the threshold, giving her eyes time to adjust to the dim interior. There had been one place her parents had patronized, a little shop on the Left Bank, with a leathery, smoky smell just such as this, where the proprietor kept coffee in the back for his favorite guests. There would be impromptu recitations and loud political arguments and above it all the smell of leather and book glue and her mother’s musk perfume.

“Owwww!” protested Gabrielle. “You poked me!”

“Did not!” Pierre-André was the picture of outraged innocence. Until he poked her again.

Laura came hurtling back from 1784. She wasn’t twelve years old anymore, trailing along in the wake of her parents from bookshop to atelier. She was a thirty-two-year-old governess and the proprietor was giving her the sort of look reserved for people who bring dangerous livestock onto the premises.

“Gentlemen,” she said severely, relocating Pierre-André to her other side, “do not poke their sisters.”

Pierre-André pouted. “But—”

“People who poke are little better than savages, and savages Do Not Get Books. Am I understood? Come on,” Laura said, taking Pierre-André by the hand. “Let’s see what we can find for you. Maybe the proprietor will have something to recommend.”

“Look! Look!” Pierre-André tugged, yanking her towards a book propped open on a stand. A black-and-white illustration portrayed an enraged Hercules whopping away at the heads of the hydra. The hydra looked justifiably alarmed.

Behind them, cold air gusted into the shop as the door opened, admitting another customer.

“If you behave, you can have it,” Laura bribed him shamelessly, propelling him towards the counter and the clerk, determined to get there first, before the new customer could beat her out.

Pierre-André seized his advantage. “Can I have sweets, too?”

The newcomer wafted his way down the narrow aisle, his head tilted at an angle that implied that he was in the process of listening to divine voices that sang only to him. He came down to earth long enough to wave a languid hand at Pierre-André. “This shop purveys celestial sweets, dear boy. The sweets of . . . learning!”

He was garbed with that deliberate air of dishabille that proclaims the artist the world over. Despite the cold, he wore no jacket, only a waistcoat over his flowing white shirt, and a rough cravat knotted at the neck.

Pierre-André was looking perturbed again. “Are those like candied almonds?”

The poet—he could only be a poet—pressed two fine-boned hands to his chest. “Better than almonds, my lively lad. In these Elysian fields one can sup on the sugared nuggets of choicest poesy.”

All but concealed behind a display of books, Gabrielle rolled her eyes. Laura heartily concurred.

Pierre-André ignored Elysian fields and went straight to the important bit. “I want nuggets of posy,” he demanded. “Sugary ones.”

Laura wanted a cup of tea. Brewed black, milk, no sugar.

“In a minute,” she said, but it was already too late. The poet had ranged himself in front of the counter. He had, she realized indignantly, cut her out. She tried tapping her foot, but the poet was oblivious.

He was more likely smoking the sugary fields of Elysium than supping on them, thought Laura bitterly. The Left Bank hadn’t changed much since her parents’ day.

“What have you today for me”—the man paused dramatically, swishing his sleeves for emphasis—“in terms of poetree?”

Laura contemplated a swift kick to the knee. Preferably times three.

The shopkeeper reached beneath the counter and drew out a slim book bound in cheap paper covers. “You might want to try this, Monsieur Whittlesby. It’s the latest from Porcelier.”

“That rubbish!” An exuberant gesture sent a full yard of white linen sleeve swooping over Pierre-André’s head. Pierre-André ducked and giggled. “The man has no feeling for the rhythm of the language, for the tripping trot of enjambed feet as they prance down that pulchritudinous path of poesy over which only the muse may rule as mistress.” The speech was made all the more impressive by the fact that the poet managed to utter it without once pausing for breath.

The shopkeeper eyed him dispassionately. “Shall I put it on your account as always, Monsieur Whittlesby?”

The poet tucked the book up beneath one flowing sleeve, where it disappeared among the folds. “Yes, do.”

Laura waited impatiently for the poet to step away from the counter, as the shopkeeper embarked upon the seemingly endless process of recording the transaction in a dog-eared ledger. Muttering to himself in rhyme, the poet wandered to the side, his nose buried in the despised poems of Porcelier. Laura could hear the occasional “Ha!” emerge from between the red morocco covers.

Laura tugged Pierre-André out from under one of the poet’s sleeves, with which he was amusing himself by playing a private game of hide and seek among the excess fabric.

“May I have my posy now?” he demanded.

Laura put a hand on his head to quiet him. “Do you have any books appropriate for a child of five?” she asked the shopkeeper.

With Pierre-André beside her, the question sounded entirely natural, not at all like a set piece she had been instructed to recite.

Clicking his tongue against his teeth, the clerk rummaged about in an untidy pile of books. It was, thought Laura, an excellent performance. If it was a performance, that was. What if this wasn’t the right clerk?

Well, then, Laura told herself, keeping a grip on a squirming Pierre-André, the worst that would happen would be that they would have bought a book appropriate for a five-year-old.

The shopkeeper held up a book, squinted at it, clicked his tongue a few times more, and returned it to the pile, repeating this process before emerging triumphant with a large, ornately bound volume.

“You might want to try this,” he suggested.

No, no, no. Laura wanted to stamp in impatience. That wasn’t the right phrase. If he were her contact, he was supposed to say, “I usually recommend this for a child of seven,” or eight or nine, with the number representing the page on which she would find the key word that would then be used to decode the message.

“Oh?” said Laura. “What is it?”

Whatever it was, she hoped Pierre-André liked it, because it obviously wasn’t going to serve any other purpose.

Placing the book flat on the counter, the shopkeeper spread it open to reveal a delicately tinted engraving of a flower.

It was an orchid.

Chapter 4

It wasn’t silver. There was no such thing as a silver orchid. But it didn’t need to be. Laura knew exactly what it meant.

A thrill of excitement buzzed through her, heady as the champagne she dimly remembered drinking back in her pre-governess days.

“It’s perfect,” she said, and meant it. There would be no need for a page indication this time. She knew what her key word would be. “Silver.” In one fell swoop, the Carnation’s contact had confirmed his status and given her the code for the next message. “Natural history, is it?”

“Many young gentlemen these days are taking up botanical pursuits,” said the shopkeeper blandly.

“Young ladies, too,” Laura said, feeling positively arch.

“So I have been told,” said the shopkeeper, with something that wasn’t quite a smile. “Some may find it unconventional, but I hear that they take to it quite well.”

Laura felt an unaccustomed urge to grin. It was all she could do not to grab the shopkeeper by the hand and shake it, babbling, haven’t we done well? Aren’t we clever?

Instead, she nodded crisply, tapping a gloved finger against the open page of the book. “It will be good drawing practice for my pupils. We’ll take it.”

Without betraying any emotion, the shopkeeper closed the cover, concealing the orchid beneath a nondescript façade of blue leather. “Will there be anything more?”

“I will also need an introductory Latin text,” said Laura. That wasn’t part of the code, but, while she was teaching, she might as well teach. It would be hard to explain her continued presence in Jaouen’s household otherwise. “Do you have the Orbis Sensualium Pictus?”

“The—?” The shopkeeper paused to allow her to fill in the title.

It was a book she had often used to teach Latin before, especially to younger children. Brightly colored pictures were paired with the corresponding Latin and English translation.

“The Orbis Sensual—” Laura ground to a halt as she realized her blunder.

The second language after the Latin in the Orbis Sensualium wasn’t French. It was English.

She had used the Orbis Sensualium Pictus to teach English children in England. How could that not have occurred to her? That was certainly one way to get herself caught in a hurry; go about asking for English books in a French bookshop. She might as well emblazon “SPY” on her forehead. In capital letters. In English. With a Latin translation underneath.