Perhaps Alberich expected that reaction from her, for he paused only for a moment before he went on. ‘The Library kept him from me, Ray. Don’t I have a right to my own flesh and blood?’

There were so many things wrong with that statement that Irene found herself incapable of answering. She snapped out of her momentary shock and whispered to the book in her hands, ‘Book that I am holding, fly up and knock that man up there from where he stands!’

The book went up like a comet, scraping her fingers with the force of its ascent. A cry of, ‘Shelves, shield me!’ and the meaty thud of an impact came from above her.

But Irene was already running. ‘Dust, hide me!’ she shouted, holding a length of tattered tulle across her nose and mouth against the rising clouds of dust.

She trailed her free hand along the bookcases lining the passage so as not to collide with them. Tears ran from her eyes as she blinked frantically, trying to see where she was going. This method of hiding herself did have a few associated problems. But at least it concealed her from Alberich.

Until he loses patience and just levels all the bookshelves in the area, her sense of incoming doom pointed out. Keep on running.

The astonishing thing was that he hadn’t done what he did once before – sinking her into the floor and calling on all sorts of chaotic forces to destroy her. If it had been Irene trying to destroy him, she’d have used whatever she had available.

Unless . . . could she have missed something here? Alberich had created this place, or at least forged it out of a Fae world so far gone into chaos that it had no firm reality left. He’d set it up in a very specific way. Did this mean that he couldn’t go round unleashing chaotic power into it randomly, any more than a mad scientist would set off dynamite in the middle of his own laboratory? It would explain a few things.

Though it wouldn’t save her, if Alberich caught up with her. Even if he left her alive in return for telling him about his . . . son. She couldn’t help flicking through a mental list of male Librarians she knew, wondering if they might be the son in question. Admittedly she was better at discussing their literary tastes than their pre-Library histories, but she didn’t think any of them could have had that sort of history.

The fog of dust blinded Irene nearly as much as it did Alberich, and she was taken by surprise as she stumbled into the central area. She was conscious of a wide-open space in front of her, even if she couldn’t see it clearly yet, and some sort of massive tangle of open dark stairs and glowing lights.

‘Bookcases!’ came a furious shriek from above her. ‘Block her way!’

The two high bookcases on either side of her bowed down and collapsed in a great landslide of shelves and books. Pages filled the air, mingling with the dust and tumbling like huge snowflakes. She had to dodge back frantically to avoid being hit by the falling bookcases, and then her way was well and truly blocked. She’d have to clamber over them, or go round – either of which would lose time and make her far too obvious.

Something that had been nagging at the back of her mind finally broke through. This is a high-chaos world. Alberich’s using the Language far more to frame his intent than in terms of precise description. And I’m doing the same. Just how far can I push this?

She gritted her teeth and braced herself. ‘Floor! Open beneath the barrier and let me pass!’

The floor groaned, then split with pained creaks and cracking, the two sides pulling apart like the edges of a wound. The resultant gap ran beneath the toppled bookcases, narrow, uneven, dark and full of splinters . . . but it looked big enough for Irene to get through. With a silent prayer that Alberich couldn’t see her and that his next words wouldn’t involve such verbs as close, smash or crush, Irene squeezed through the crack. She had to lower her head and wriggle sideways, and with every panting breath it seemed that the riven floor was pressing in on her and about to squeeze shut.

She broke through to the other side with a gasp of relief. The dust was not so thick or noxious now – perhaps the barrier of bookshelves had blocked it off, or maybe it was simply settling of its own accord – and she could see the construction at the heart of Alberich’s library.

It was an openwork tangle of metal stairs and books, perhaps a hundred yards across at first glance. The stairs writhed around each other, ignoring such petty constraints as railings or supports and rising several storeys high at the corners. The books gleamed amid the dark metal, scattered through the network in some sort of pattern and glowing with their own light. And in the middle of the pattern of books and stairs was the clock, which was still ticking. It was a shadowy clock face hanging in the air, with ivory-pale hands that moved ever closer towards midnight. It didn’t give off any sort of gleam or glow. Instead it was a point of immense darkness, the sort of thing that Irene imagined a black hole might look like if given physical form and shrunk to such a tiny scale. And it wasn’t Irene’s imagination that it was ticking faster.

Before the clock reaches midnight, Alberich had said. She was almost out of time.

All sorts of options presented themselves. Stopping the clock or moving the books were the most obvious. Irene ran for the nearest flight of stairs. Her feet rang on the metal steps as she sprinted up them. Fatigue had vanished, now that she was so close to success.

She made it to the first landing, where one of the books waited, on display. The part of her mind that became distracted during moments of life-threatening danger couldn’t help wondering about it. It must be one of the unique specimens Alberich had stolen. Where was it from, who was the author, what was the title – and if and when this was all over, would she ever get the chance to read it?