Now she stood at a street corner, trying to ignore the gales of ribald laughter coming from the public house in front of her, and asked the girl again, ‘Are you sure you’ve never heard of him? His father’s a drayman. He’s about nineteen, twenty perhaps – he’s lived here all his life.’

‘I’m sorry, darlin’,’ said the girl. She eyed Rosa speculatively through her lashes and Rosa saw, to her shock, that the girl’s lips and eyelids were painted. ‘Someone’s bin telling you porkies.’

‘Porkies?’ Rosa echoed stupidly. She felt close to tears.

‘Pork pies – lies. Ain’t you never heard of rhyming slang?’ She made a face and laughed. Rosa felt her cheeks grow hot.

‘I’m sorry. I won’t waste your time any further.’

‘Not to worry, darlin’. But if your boyfriend lived round here, I’da heard of him. There’s not many men round here unacquainted with Phoebe Fairbrother.’ She gave a raucous laugh.

‘Would your friend know anything?’ Rosa pleaded, nodding at the brunette seated in the tavern window. The girl shook her head, impatiently now, setting her brassy curls swinging.

‘If I ain’t heard of him, Miriam won’t know ’im neither. I’m telling you, there ain’t no Luke Welling round ’ere. The only Lukes what live in this district is Lucas Michaels, but he’s fifty if he’s a day, and Luke Lexton. Now, if you’ll excuse me, I’ve got my customers to attend.’

She turned, but before she could go Rosa grabbed her arm.

‘Wait. What did you say? Luke Lexton?’

‘It’s clear you ain’t deaf anyhow.’

‘I’ve heard that name. Oh, God, where have I heard it?’ She shut her eyes, desperately scrabbling for the memory. She had heard it, recently too . . . It came to her suddenly – Minna, in the factory, asking ‘Luke Lexton?’ when she had mentioned Luke’s name. And she hadn’t even noticed.

‘Luke Lexton!’ she cried. ‘Yes! That’s it, I made a mistake. I should have said Luke Lexton, not Welling. Do you know where he is?’

‘Made a mistake, didja?’ The girl snorted disbelievingly, but there was a smile at the corner of her mouth. ‘What do you want with Luke Lexton then? You’d need two more legs for him to take notice of you.’

‘What?’ Rosa said, too confused to be polite.

‘He’s sweeter on horses than women,’ Phoebe said. ‘Not that I wouldn’t give him a ride, if he came asking.’

Rosa knew she should pretend to be shocked, but she didn’t care.

‘Where does he live?’

‘At his uncle’s forge, off Farrer’s Lane. But his father’s no drayman – he’s dead.’

‘Farrer’s Lane – where’s that? Can you – would you show me?’

‘Why should I?’ The girl folded her arms and Rosa felt desperate. ‘I’m a working girl, darlin’. I get paid for my time.’

‘I don’t have any money!’ She could force Phoebe to tell her. That was dark magic, but she had seen the spells in the Grimoire, although Mama had told her never to look at those pages. If only she had a coin . . .

Phoebe looked her up and down appraisingly, her eyes hard. She seemed to come to a decision.

‘Give me that locket.’

‘What? No!’ Rosa’s hand closed around it reflexively. She felt its heavy warmth against her collarbone, where it had rested since Papa had given it to her on her tenth birthday. ‘You don’t understand . . .’

‘I understand that you want a service and you’re not prepared to pay for it. But I don’t care, wander the streets of Spitalfields on your own; you’ll soon find some kind fella prepared to take you under his wing, no doubt.’ She gave a raucous laugh and Rosa bit her lip. She could well imagine what kind of fellows she might meet in the dark streets between here and Luke’s uncle’s forge. They were spilling out of the Cock Tavern now, amorous and angry by turns. One of them plucked at Phoebe’s sleeve.

‘Gi’s a tumble, Phoebs, for old time’s sake, eh?’

‘Oh piss off, Nick Sykes, you old soak,’ the girl snarled. She gave him a shove and he stumbled backwards, tumbling into the filth-filled gutter where he lay, laughing or sobbing, Rosa could not tell which. Phoebe turned back to Rosa. ‘Well? Take it or leave it, I ain’t got the time to be gabbing here.’

‘I’ll take it,’ Rosa said, though her heart hurt as she fumbled for the catch of the locket. Phoebe reached for it, greedily, and Rosa said, ‘Wait!’

She opened it up and, using her nail, prised out the tiny pencil drawing of Papa. She saw now that it was crude, the work of a child. But it was all she had.

For a moment the locket hung from her fingers, still hers. Then she let it drop into Phoebe’s outstretched palm.

Phoebe nodded.

‘Come on then. Look slippy and don’t talk to no one. You’re like a fox in a hen house. No, hang about, that’s the wrong way round. But there ain’t no such thing as a fox house.’

But perhaps Phoebe had it right, Rosa thought, as she followed her down the first dark alleyway between two buildings. She was more dangerous, more predatory than any of the poor drunkards. She could gut them alive if she chose. She was aware, suddenly, horribly, of the power even the feeblest witch held over the outwith. No wonder their kind had been hated and feared for so long.

Phoebe was cheerful now, chatting as she led Rosa through stinking back alleys, where children played in spite of the filth and the darkness. They cut across the corner of a deserted market space, where a few beggars were rummaging in the cast-off boxes, and then up a street less forbidding than the rest, if only because it was emptier. The evening fog had begun to descend and Rosa shivered, wishing that she had not left her wrap in the carriage. What would the driver be thinking? Would Sebastian have noticed her absence?

Then suddenly Phoebe swung left through a low arch and into a cobbled yard. There was a roaring sound, as of a huge fire, coming from a low brick building to their right, and a shower of sparks flew up suddenly from the chimney.

‘Luke,’ Phoebe yelled. ‘Gotta visitor.’

‘Who is it?’ The voice was so familiar that Rosa choked. She could not speak.

Phoebe stuck her head through the door to the forge.

‘La-di-da type by the name of . . .’ She looked back over her shoulder at Rosa. ‘What was your name, darlin’?’

‘Rosa,’ she whispered. ‘Rosa Greenwood.’

‘Rosa Greenwood,’ Phoebe repeated back. There was a reply that Rosa could not hear and Phoebe shrugged and turned back to Rosa.

‘Says he’s never heard of you. Well, there you are. Not my fault if you made a mistake. Anyway, I’ve done what I said. Tarra now.’

And with a swish of skirts and a flash of scarlet petticoat, she was gone.

Rosa took a deep breath and stepped forward into the forge. For a minute she almost didn’t recognize the man working the bellows. He was stripped to the waist, sweating, his muscles standing out in the light from the fire, the flames flickering across his naked chest and shoulders. His head was down, his brows knit in effort or concentration.

Then he looked up and she saw his clear hazel eyes.

He wiped his brow with a cloth and then took a shirt from a peg by the door and pulled it over his head.

‘Yes, miss,’ he said as he tucked it in. His voice at least was familiar, the same low voice she remembered, though his East End accent sounded stronger than it had in Knightsbridge. ‘What can I do for you? My uncle’s not here, as you see.’

‘Luke . . .’ She didn’t know where to begin, how to start. ‘Luke, it’s me, Rosa.’

Something flickered in his eyes, not recognition, but a kind of wariness.

‘I’ve never seen you before,’ he said flatly.

‘That’s not true.’ What could she say? How could she convince him? She had taken everything, every memory of herself, of why he had come, of what had happened to him there. ‘I know things about you.’

‘Like what?’

‘I know that you’ve lost your memory, that you can’t remember anything for the last month back, maybe longer. I know that you have a scar on the back of your head, that you came back with a wound there, from a fight.’

‘Anyone could know that,’ he said hoarsely, though he looked uneasy. ‘You could have talked to Phoebe.’

‘I know that you have a mark on your shoulder.’ She thought of him washing under the pump in the yard. ‘A scar, like a brand.’

His hand went involuntarily to the place and then he shook his head.

‘You saw it while I was dressing, just now.’

‘Luke, why won’t you believe me?’ It was not what she wanted to ask; she wanted to shake him, ask why he’d come to Osborne House, why he had changed his name and lied about his father. Had it all been a lie? No – she thought of his confession, in the dark of the stable yard. His uncle and the forge – that had not been a lie. And she remembered his other confession. About what he could see.

‘I know something else,’ she whispered. ‘I know that you – that you . . .’ She swallowed. ‘I know that you can see witches.’

He flinched, as if she had slapped him.

‘It’s true, isn’t it?’

‘How do you know?’ he demanded. He was across the forge in an instant, grabbing her arms with a strength that almost frightened her, except that it was Luke, Luke who would never hurt her.

‘I know b-because . . . I am one.’

She let her magic shine out, feeling it flicker across her skin like electricity, flow through her limbs and her fingers, crackling to the tips of her hair like static energy.

Luke let go of her as if she had burnt him. He was staring at her with a look of horror. His hand went again to the scar on his shoulder as if it hurt.

Rosa stretched out her hands, where the witchlight burnt, clear and bright in her palm.