‘Mm. Your argument would appeal to any bibliophile, Miss Winters. Should I take it that you are here in pursuit of a particular book?’

Irene nodded again. ‘The copy of Grimm that Lord Wyndham had before his death. But it seems that we aren’t the only people after it.’

Vale hesitated for a long moment. ‘Very well. I can postulate an interdimensional library hunting down rare books. I can accept the agents of that library having unusual powers.’ He glanced at Kai. ‘Once one accepts the basic concept as possible, today’s events become – well, not entirely inexplicable. I have a great many questions, but one query in particular intrigues me, and I trust that you can give me a solid answer to it. Why should you be looking for Grimm’s Fairy Tales? Why not the latest scientific advances?’

Irene smiled. This part had always warmed her somewhere deep inside. She leaned forward in turn, putting her cup down. ‘Mr Vale, while all the alternate worlds exist, and while they may have different metaphysical laws, their physical laws are the same. Iron is iron, radium is radium, gunpowder is gunpowder, and if you drop an object, it will fall according to the law of gravity. Scientific discoveries are the same across the alternates, and while they are no doubt important, we don’t value them as we do creative work. There may be a hundred brothers Jakob and Wilhelm Grimm in a hundred different worlds, and each time they may have written a different set of fairy tales. That’s where our interest lies.’

Vale blinked. ‘But in that case, you could import the discoveries from other worlds! You could bring more than simply fiction – new technologies, new wonders of science. Have you no concept of the good you could do for these – ’ he remembered himself – ‘hypothetical alternate worlds.’

‘Wouldn’t work,’ Kai said, staring at his tea.

‘What my colleague is trying to say,’ Irene said patiently, ‘is that, while it has been tried, firstly, the Library does not care to make itself public. Secondly, we cannot introduce material for which there is no support infrastructure. This is what would happen if we tried to bring in discoveries that your current science didn’t support, and as a result the discovery wouldn’t take root. It would probably be written off as a fake in short order. Also, please consider. What would be the dangers facing a person attempting to introduce entirely new scientific knowledge to this world? To this country?’

Vale nodded slowly, his expression bitter. ‘I take your point,’ he said. He didn’t sound convinced, though.

‘And lastly,’ Irene said, a little embarrassed that she had to point it out, ‘all of us who are sealed to the Library are people who have chosen this way of life because we loved books. None of us wanted to save worlds. I mean, not that we object to saving worlds . . .’ She shrugged, picking up her teacup again. ‘We want books. We love books. We live with books. Someone who joined the Library just so that they could try to use the Library to benefit their own world . . . well, I suppose it would be ethical, but it isn’t the purpose of the Library.’

‘Then what is the purpose of the Library?’ Vale asked.

‘To save books,’ Irene said firmly. The words were so automatic that she didn’t even need to think about them. She’d spent all her life with the idea. But they had never sounded hollow to her before. She made herself focus on the familiar justification. ‘To save created works. In time, if their original alternate loses them, we can give them back copies, so that they aren’t lost. And in the meantime, the Library exists and endures.’

‘So why did Alberich leave?’ Vale asked.

Irene swallowed. She hadn’t expected him to get to that point quite that fast. The little that she knew about Alberich was bad enough that she had been happy to write him off as a myth. She didn’t really want to think of him as a real person with potentially terrifying motivations. Then she blinked. ‘Wait. How did you know that?’

Vale waved a hand dismissively. ‘Simple enough. The fellow is clearly a deserter from your own organization. Given what I know about it from you, his possible motives are either personal advantage, or he has overarching principles that conflict with your own stated mission – which is to save books and not interfere in the workings of other worlds. But if it were a question of personal advantage, why bother to hunt down and assassinate other Librarians? If he wanted money, fame or adventure, presumably other Librarians wouldn’t get in his way, as long as he didn’t obstruct your searches for specific books. And what specific book would be that important to him, if he were pursuing personal gain? So perhaps he has a larger plan, one that requires your non-interference. This would require him to be motivated by personal power or have some goal which he believes is more important than your Library’s search for books. Your own response confirms this – why else would Library agents feel such a sense of dread towards a mere rogue agent?’

Irene reminded herself bitterly not to underestimate Vale again. She also ignored Kai, who was twiddling his fingers in his lap with an air of smug unconcern. Fine. I suppose I should be glad his mood’s improving. ‘Alberich left the Library a while ago,’ she said reluctantly. ‘I lack the clearance for full information on why.’ Or any information beyond the bare minimum.

‘So – this Alberich is a continual threat. Has he crossed your path before?’

Irene shook her head. ‘No. Thank heavens. I had heard about him, of course, everyone hears about him—’