‘You did it,’ he said, when he caught sight of her, followed by a word she didn’t understand. ‘You really did it. The Dragon.’

‘You helped,’ Alice said.

‘Only after you persuaded me not to lay down and die.’ Isaac sat up, rubbing his eyes with the sleeves of his coat, which left dark stains of dirty grit across his cheeks. ‘I would have . . . I don’t know. I didn’t think it was possible.’

‘Neither did I,’ Alice said truthfully. ‘But my father always said there’s no percentage in hanging about.’

They fell into silence. Isaac’s eyes went to the book, which Alice still clutched tightly to her chest. He looked away, sighed, and rolled to his feet, groaning like he’d aged sixty years. Alice levered herself up with one hand, unwilling to release the book even for a moment. Her feet – bare again, she noticed – swept up the dust of the library floor.

Behind them was the table, still bearing the hurricane lamp. Above it, faint and spectral, Alice could see the wraithlike Siren, and a faint hint of her music still pervaded the air. Isaac found the other lamp lying where he’d dropped it in their scuffle. He picked it up and made a futile attempt to pat the dust off his trousers.

‘Well?’ Alice said. ‘What now?’

‘I’ll go back to my master,’ Isaac said. ‘I haven’t got the book, but I have got the Dragon. That ought to count for something.’ He hesitated. ‘You’ve got it too, haven’t you?’

Alice felt around at the back of her mind. There were three threads there now – the silver one belonging to the Swarm, the wooden tendril of the tree-sprite, and another, black and shining like obsidian. Even without touching it, she could feel it thrumming with power. Taking hold of it sent a thrill through her essence, like licking a live battery, but when she gave it a tentative tug, it barely shifted.

‘We were both in the book when it submitted to us,’ Isaac said. ‘I don’t think I’ll have the power to use it if I live a thousand years.’ He sounded a little in awe. ‘But . . .’

Alice was silent. She could feel Isaac, she realized, feel his touch on the thread. It ran through both of them, and back to the book she clutched under her arm. It wasn’t a connection of minds, or even voices; just a sense of contact, like sitting side by side on a bench with their hands intertwined. She found herself smiling, a little inanely, and realized he was doing the same.

‘And you?’ Isaac said. ‘What will you do?’

She shook her head. ‘I don’t know.’