Vespidian! She was sure she could make out the fairy’s nasal drone, and the deeper voice of Mr Black. Before she could think about it, she’d sent the swarmer through the door, hopping over the lintel and pushing through the gap. The door swung where she brushed it, very slightly, and gave a creak that sounded very loud in the little creature’s ears. Alice stopped, and spent a moment listening, but the sound of conversation drifted up undisturbed.

The feeling of weight was getting stronger the further she went, but she could hear the drone of the fairy’s wings now, and a crackling sound that might have been a fire. A short corridor led past a gaslight and turned a corner, and then she was facing another flight of stairs. At the bottom, outlined in a glowing doorway, stood Mr Black, with the smaller figure of Vespidian hovering in the air in front of him.

‘. . . you’re sure the map works?’ the fairy said, in his high, nasal voice.

‘I got it straight from the Bone Oracle,’ Mr Black rumbled. ‘It had better work, considering what it cost me. She drives a hard bargain, but I called in a couple of old favours. I couldn’t try it in the library, but it shows the start of the path, no problem.’

‘That doesn’t mean much,’ Vespidian said dubiously. ‘It’s only inside the labyrinth that things get tricky.’

‘Don’t use it, then,’ Mr Black spat. ‘Search every book by hand, for all I care. As long as I get what’s coming to me.’

‘All right, all right,’ the fairy said. ‘No need to get huffy. Let’s have it, then.’

‘No.’

There was a sharp intake of breath, and a long silence. Alice perched the swarmer on the edge of the first step, straining to hear.

‘What do you mean, no?’

‘I mean that it’s about time for a show of good faith on your part.’ Mr Black waved one huge finger in the fairy’s face, and Vespidian buzzed backwards. ‘I’ve done everything you wanted, haven’t I? I got you in here, I kept you secret, and now I’ve got you the map. I even tipped you off about the girl and her father, for all the good it did you.’

Alice’s breath froze in her throat, and the swarmer wobbled.

‘Once I hand it over’ – Mr Black waved at the door behind him, where the fire was burning – ‘there’ll be nothing keeping you from grabbing this book you want so badly and scurrying back home. So you go and tell your master that Mr Black wants what he’s owed, and he wants it now. Once he delivers, then you can have the map, and good luck to you. Until then . . .’ He crossed his enormous arms and waited impassively.