‘Rosa?’ He clutched her, hardly able to believe she was alive, and she cried out, pulling her arm from his grip.

‘My arm!’ She held it up ruefully, looking at the weeping skin and broken blisters. ‘God, for a bit of magic to take the edge off . . .’

‘But – but you were cold!’

‘I am cold.’ She rubbed her hands and then touched his. ‘So are you.’ She shivered and then winced again. ‘Oh, my arm . . .’

‘Why can’t you heal it?’

‘I’m spent. Magic’s like . . . it’s like strength, in a way. If you asked me to lift that beam now, I doubt I could. My muscles are like wet wool. It’ll come back, but for now – I couldn’t conjure so much as a witchlight.’

She looked down at her scorched and blistered palm and Luke remembered the stable, the frail white glow in her hand . . .

‘You saved me,’ he said slowly. ‘I tried to kill you – and you saved me. Why? I deserve to burn for what I tried to do to you.’

‘You came back for me,’ she said simply.

For a long time they said nothing, just sat side by side in the ruins of Sebastian’s factory, looking out to the river and the boats drifting past. It was still early, the sky pale in the east, but Luke could hear the cries from the waterfront drifting downriver and he knew that the East End never really slept.

‘We must get going.’ He stood, painfully, feeling his exhausted muscles complaining and his stiff joints cracking. His hurt leg screamed as he stood, but it was not broken – just stiff and sprained. He put out a hand and Rosa scrambled to her feet and stood brushing down her charred silk gown with a rueful face. ‘Where will you go?’ he asked.

‘I don’t know.’

‘Well, we can’t stay here.’ Luke looked at the sky and then the river. ‘The police will come soon. And Knyvet will be back.’

Rosa shivered.

‘He has everything now: Southing, the factories, the Chair . . . But not me. And he would kill me for that, if he found out I was still alive. I cannot go home. Can we go back to your uncle’s? To the forge?’

‘No.’ Luke shook his head. ‘I told you, I was sent to kill you – the price for failing was death. My death.’

‘So, your people are as barbaric as mine,’ she said softly.

‘Not William,’ Luke said. He swallowed against the pain in his smoke-scorched throat. ‘William loves me. But I can’t – I can’t make him choose between me and the Brotherhood. I must go my own way, alone now.’

‘So must I.’ She took his hand and a faint prickle of magic, like a flame, lit her face for a moment, like a ray of warmth in this dreary fog-muted dawn. ‘So we are not alone.’

Luke nodded.

They turned, and together they began to walk towards the rising sun.