He had only once before felt this sense of closeness to a woman. That was Amelie, lost these many years . . . He felt a sudden thump as his heart skipped a beat. Had she been with child? Was that the reason he had felt so? But there was nothing to be done about it now.

Madeleine had begun to relax against him, her hands at last leaving her belly. He kissed her, with a real feeling of affection.

‘It will be beautiful,’ he whispered to her. ‘And once you are well and truly with child, I will buy your contract from Fabienne and take you away. I will buy you a house.’

‘A house?’ Her eyes went round. They were green, a deep, clear emerald, and he smiled at her again, stepping back.

‘Of course. Now, go and sleep, my dear. I shall come again tomorrow.’

She flung her arms around him, and he had some difficulty in extracting himself, laughing, from her embraces. Normally, he left a whore’s bed with no feeling save physical relief. But what he had done had made a connection with Madeleine that he had not experienced with any woman save Amelie. Well . . . and Mélisande, too, now that he thought . . .

Mélisande. A sudden thought ran through him like the spark from a Leyden jar. Mélisande.

He looked hard at Madeleine, now crawling happily naked and white-rumped into bed, her wrapper thrown aside. That bottom . . . the eyes, the soft blonde hair, the gold-white of fresh cream.

‘Chérie,’ he said, as casually as he might, pulling on his breeches, ‘how old are you?’

‘Eighteen,’ she said, without hesitation. ‘Why, monsieur?’

‘Ah. A wonderful age to become a mother.’ He pulled the shirt over his head and kissed his hand to her, relieved. He had known Mélisande Robicheaux in 1744. He had not, in fact, just committed incest with his own daughter.

It was only as he passed Madame Fabienne’s parlour on his way out that it occurred to him that Madeleine might possibly still be his granddaughter. That thought stopped him short, but he had no time to dwell on it, for Fabienne appeared in the doorway and motioned to him.

‘A message, monsieur,’ she said, and something in her voice touched his nape with a cold finger.

‘Yes?’

‘Monsieur Grenouille begs the favour of your company, at midnight tomorrow. In the square before Notre Dame de Paris.’

They didn’t have to practise custody of the eyes in the market. In fact, Sister George-Mary, the stout nun who oversaw these expeditions, warned them in no uncertain terms to keep a sharp eye out for short weight and uncivil prices, to say nothing of pickpockets.

‘Pickpockets, Sister?’ Mercy had said, her blonde eyebrows all but vanishing into her veil. ‘But we are nuns – more or less,’ she added hastily. ‘We have nothing to steal!’

Sister George’s big red face got somewhat redder, but she kept her patience.

‘Normally, that would be true,’ she agreed. ‘But we – or I, rather – have the money with which to buy our food, and once we’ve bought it, you will be carrying it. A pickpocket steals to eat, n’est-ce pas? They don’t care whether you have money or food, and most of them are so depraved that they would willingly steal from God himself, let alone a couple of chick-headed postulants.’

For Joan’s part, she wanted to see everything, pickpockets included. To her delight, the market was the one she’d passed with Michael, on her first day in Paris. True, the sight of it brought back the horrors and doubts of that first day, too – but for the moment, she pushed those aside and followed Sister George into the fascinating maelstrom of colour, smells, and shouting.

Filing away a particularly entertaining expression that she planned to make Sister Philomène explain to her – Sister Philomène was a little older than Joan, but painfully shy and with such delicate skin that she blushed like an apple at the least excuse – she followed Sister George and Sister Mathilde through the fishmongers’ section, where Sister George bargained shrewdly for a great quantity of sand dabs, scallops, tiny grey translucent shrimp, and an enormous sea-salmon, the pale spring light shifting through its scales in colours that faded so subtly from pink to blue to silver and back that some of them had no name at all – so beautiful even in its death that it made Joan catch her breath with joy at the wonder of creation.

‘Oh, bouillabaisse tonight!’ said Mercy, under her breath. ‘Délicieuse!’

‘What is bouillabaisse?’ Joan whispered back.

‘Fish stew – you’ll like it, I promise!’ Joan had no doubt of it; brought up in the Highlands during the poverty-stricken years following the Rising, she’d been staggered by the novelty, deliciousness and sheer abundance of the convent’s food. Even on Fridays, when the community fasted during the day, supper was simple but mouthwatering, toasted sharp cheese on nutty brown bread with sliced apples.

Luckily, the salmon was so huge that Sister George arranged for the fish-seller to deliver it to the convent, along with the other briny purchases, and so they had room in their baskets for fresh vegetables and fruit, and so passed from Neptune’s realm to that of Demeter. Joan hoped it wasn’t sacrilegious to think of Greek gods, but she couldn’t forget the book of myths that Da had read to her and Marsali when they were young, with wonderful hand-coloured illustrations.

After all, she told herself, you needed to know about the Greeks, if you studied medicine. She had some trepidation still at the thought of working in the hospital, but God called people to do things, and if it was His will, then—

The thought stopped short as she caught sight of a neat dark tricorne with a curled blue feather, bobbing slowly through the tide of people. Was it— it was! Léonie, the sister of Michael Murray’s dead wife. Moved by curiosity, Joan glanced at Sister George, who was engrossed in a huge display of fungus – dear God, people ate such things? – and slipped around a barrow billowing with green sallet herbs.

She’d meant to speak to Léonie, ask her to tell Michael that she needed to talk to him. Postulants were permitted to write letters to their families only twice a year, at Christmas and Easter, but he could send a note to her mother, reassuring her that Joan was well and happy.

Surely Michael could contrive a way to visit the convent . . . but before she could get close enough, Léonie looked furtively over her shoulder, as though fearing discovery, then ducked behind a curtain that hung across the back of a small caravan.

Joan had seen gypsies before, though not often. A dark-skinned man loitered nearby, talking with a group of others; their eyes passed over her habit without pausing, and she sighed with relief. Being a nun was as good as having a cloak of invisibility in most circumstances, she thought.

She looked round for her companions, and saw that Sister Mathilde had been called into consultation regarding a big warty lump of something that looked like the excrement of a seriously diseased hog. Good, she could wait for a minute longer.

In fact, it took very little more than that, before Léonie slipped out from behind the curtain, tucking something into the small basket on her arm. For the first time, it struck Joan as unusual that someone like Léonie should be shopping without a servant to push back crowds and carry purchases – or even to be in a public market. Michael had told her about his own household during the voyage – how Madame Hortense, the cook, went to the markets at dawn, to be sure of getting the freshest things. What would a lady like Léonie be buying, alone?

Joan slithered as best she could through the rows of stalls and wagons, following the bobbing blue feather. A sudden stop allowed her to come up behind Léonie, who had paused by a flower stall, fingering a bunch of white roses.

It occurred suddenly to Joan that she had no idea what Léonie’s last name was, but she couldn’t worry about politeness now.

‘Ah . . . madame?’ she said tentatively. ‘Mademoiselle, I mean?’ Léonie swung round, eyes huge and face pale. Finding herself faced with a nun, she blinked, confused.

‘Er . . . it’s me,’ Joan said, diffident, resisting the impulse to pull off her veil. ‘Joan MacKimmie?’ It felt odd to say it, as though ‘Joan MacKimmie’ was truly someone else. It took a moment for the name to register, but then Léonie’s shoulders relaxed a little.

‘Oh.’ She put a hand to her bosom, and mustered a small smile. ‘Michael’s cousin. Of course. I didn’t . . . er . . . how nice to see you!’ A small frown wrinkled the skin between her brows. ‘Are you . . . alone?’

‘No,’ Joan said hurriedly. ‘And I mustn’t stop. I only saw you, and I wanted to ask—’ It seemed even stupider than it had a moment ago, but no help for it. ‘Would you tell Monsieur Murray that I must talk to him? I have something – something important – that I have to tell him.’

‘Soeur Gregory?’ Sister George’s stentorian tones boomed through the higher-pitched racket of the market, making Joan jump. She could see the top of Sister Mathilde’s head, with its great white sails, turning to and fro in vain search.

‘I have to go,’ she said to the astonished Léonie. ‘Please. Please tell him!’ Her heart was pounding, and not only from the sudden meeting. She’d been looking at Léonie’s basket, where she caught the glint of a brown glass bottle, half-hidden beneath a thick bunch of what even Joan recognised as black hellebores. Lovely, cup-shaped flowers of an eerie greenish-white – and deadly poison.

She dodged back across the market to arrive breathless and apologising at Sister Mathilde’s side, wondering if . . . She hadn’t spent much time at all with Da’s wife – but she had heard her talking with Da as she wrote down receipts in a book, and she’d mentioned black hellebore as something women used to make themselves miscarry. If Léonie were pregnant . . . Holy Mother of God, could she be with child by Michael? The thought struck her like a blow in the stomach.

No. No, she couldn’t believe it. He was still in love with his wife, anyone could see that, and even if not, she’d swear he wasn’t the sort to . . . but what did she ken about men, after all?

Well, she’d ask him when she saw him, she decided, her mouth clamping tight. And ’til then . . . Her hand went to the rosary at her waist and she said a quick, silent prayer for Léonie. Just in case.

As she was bargaining doggedly in her execrable French for six aubergines (wondering meanwhile what on earth they were for, medicine, or food?), she became aware of someone standing at her elbow. A handsome man of middle age, taller than she was, in a well-cut dove-grey coat. He smiled at her, and touching one of the peculiar vegetables, said in slow, simple French, ‘You don’t want the big ones. They’re tough. Get small ones, like that.’ A long finger tapped an aubergine half the size of the ones the vegetable-seller had been urging on her, and the vegetable-seller burst into a tirade of abuse that made Joan step back, blinking.

Not so much because of the expressions being hurled at her – she didn’t understand one word in ten – but because a voice in plain English in her head had just said clearly, ‘Tell him not to do it.’

She felt hot and cold at the same time.

‘I . . . er . . . je suis . . . um . . . merci beaucoup, monsieur!’ she blurted, and turning, ran, scrambling back between piles of paper narcissus bulbs and fragrant spikes of hyacinth, her shoes skidding on the slime of trodden leaves.

‘Soeur Gregory!’ Sister Mathilde loomed up so suddenly in front of her that she nearly ran into the massive nun. ‘What are you doing? Where is Sister Miséricorde?’

‘I . . . oh.’ Joan swallowed, gathering her wits. ‘She’s— over there.’ She spoke with relief, spotting Mercy’s small head in the forefront of a crowd by the meat-pie wagon. ‘I’ll get her!’ she blurted, and walked hastily off before Sister Mathilde could say more.

‘Tell him not to do it.’ That’s what the voice had said about Charles Pépin. What was going on? She thought wildly. Was Monsieur Pépin engaged in something awful with the man in the dove-grey coat?

As though thought of the man had reminded the voice, it came again.

Tell him not to do it, the voice repeated in her head, with what seemed like particular urgency. Tell him he must not!

‘Hail Mary, full of grace, the Lord is with thee, blessed art thou among women . . .’ Joan clutched at her rosary and gabbled the words, feeling the blood leave her face. There he was, the man in the dove-grey coat, looking curiously at her over a stall of Dutch tulips and sprays of yellow freesias.

She couldn’t feel the pavement under her feet, but was moving toward him. I have to, she thought. It doesn’t matter if he thinks I’m mad . . .

‘Don’t do it,’ she blurted, coming face to face with the astonished gentleman. ‘You mustn’t do it!’

And then she turned and ran, rosary in hand, apron and veil flapping like wings.

Rakoczy couldn’t help thinking of the cathedral as an entity. An immense version of one of its own gargoyles, crouched over the city. In protection, or threat?

Notre-Dame de Paris rose black above him, solid, obliterating the light of the stars, the beauty of the night. Very appropriate. He’d always thought that the Church blocked one’s sight of God. Nonetheless, the sight of the monstrous stone creature made him shiver as he passed under its shadow, despite the warm cloak.

Perhaps it was the cathedral’s stones themselves that gave him the sense of menace? He stopped, paused for a heartbeat, and then strode up to the church’s wall and pressed his palm flat against the cold limestone. There was no immediate sense of anything, just the inert roughness of the rock. Impulsively, he shut his eyes and tried to feel his way into the rock. At first, nothing. But he waited, pressing with his mind, a repeated question: Are you there?