‘We can’t possibly know how Aubrey tried to handle Alberich,’ she finally said. ‘I believe the Aubrey I met was simply Alberich disguised. I never even met the real man. All I know is that I am not going to get into a fight which I can’t win, when there are alternatives.’

Vale nodded towards the exit. ‘Through that way, then straight on for the next seven rooms, then turn left. Very well. I accept your judgement. Can you fetch help rapidly?’

Irene was glad she could agree. ‘From what I’ve heard, the main problem is that my superiors rarely know where Alberich is. If they can actually pinpoint him to this world, then they can take steps—’

Vale cut in, and Irene realized it was a sign of his urgency that he’d actually interrupt. ‘Miss Winters! A little logic, if you please. They already know he is in this world, as they warned you about him.’

Something in Irene’s stomach went cold. ‘Oh,’ she said. She hadn’t thought that through. ‘Maybe – maybe they just suspected he was here, but had no actual proof . . .’

Vale didn’t say anything, but then again, he didn’t need to, as Irene could feel the shallowness of her reasoning. Oh, it was fashionable among Librarians of her age to impute dubious motives to their seniors. She’d heard the gossip – they’d use us as bait if they thought it was necessary, they edit the information they give us, they’d sacrifice us to get their hands on a text. But that didn’t mean they believed it. At the bottom of her heart, Irene had faith in her superiors.

Genuine doubt was worse than fashionable adolescent doubt had ever been.

‘And possibly I’ve been misinformed,’ she said, forcing firmness into her voice. ‘Can we at least assess the situation before we start assuming the worst?’

‘As you wish,’ Vale said, in tones stating I know perfectly well you aren’t going to stop thinking about it now. ‘But why wouldn’t he be in his office, though we might wish him elsewhere?’

‘The automaton attack at the museum,’ Kai suggested. ‘If that was him, and if he expected to find the book there, wouldn’t he be on the spot to collect it?’

Vale rubbed his chin thoughtfully. ‘That assumes that he was responsible for the automaton attack. And it would be rather overly controlling, wouldn’t you say, to be there in person if he could command underlings . . .’

‘He did try to drown us in person,’ Kai answered. ‘Isn’t that the sort of thing that people usually have their subordinates do?’

‘True, true.’ Vale’s frown lightened. ‘If that should be so, let us by all means take advantage of it. And if not, well, I believe we may have the advantage in that he will not be expecting us. In either case, surprise and speed are our best option.’ He looked around at the vast quantity of rather dull Romano-Celtic objects in the room, noting, ‘And I do believe we are almost there.’

‘We should clear the area,’ Kai said firmly.

‘We can’t without raising the alarm,’ Irene pointed out. If Alberich were in the immediate area, he’d react to something like fire alarms going off, security guards clearing the area, or any sort of disturbance involving people running round shrieking. And people always ended up running round shrieking. It was a law of nature or something. She wondered if she could use the Language to pre-warn them as to whether or not Alberich was in his office. Nothing came to mind. ‘I think we’ll just have to knock on the door and play innocent.’

‘Hm. I believe it might work,’ Vale agreed. ‘He has no reason to believe you have penetrated his imposture. I will hold back and be ready with my gun.’

Irene tried to think of how this plan might go wrong. Alberich couldn’t have laid any sort of kill-everyone-who-touches-the-door spell on his office door (assuming that such a spell existed, something about which she had no clue whatsoever). That would be too likely to slaughter innocent British Library staff and visiting children. So that was positive. What he might have done – what she would have done if she knew how – would be to set a ward against Language use. Again, she had no idea whether or not it was possible, but she would assume for the moment that it was. So she should avoid the Language for the moment.

This bit of paranoid planning had helped her stroll through a number of Dark Ages exhibits without looking as panicked as she felt. Now, at last, their goal was through some last cases, then directly on the left.

Irene took a deep breath. She gathered her determination, smiled blandly at Kai and Vale, then strolled forward. She tried to ignore the grandfather with a complaining brat to her right and the students over by the archway ahead. Possible witnesses also included the woman squinting near-sightedly at a display card, who did look vaguely familiar – maybe she’d seen her before when she came here last time – oh dear, she was procrastinating again, wasn’t she?

Why couldn’t this be the sort of story where she kicked the door down and burst in with a loaded gun? Probably because it was a heavy door, she was in long skirts, and she didn’t have a loaded gun.

Plastering her best look of sincere concern and gullibility on her face, she knocked on the door.

No answer.

She knocked again. A couple of the bystanders glanced across, then turned back to whatever they’d been doing.

Still no answer.

‘Cover me,’ Kai said in a low voice. He stepped forward, fishing a thin metal probe out of an inner pocket. He tapped it against the doorknob as Irene shielded him from view. She glanced around but nobody was paying them any attention – except for Vale, who was hanging back and ostensibly ignoring them.