Kai casually stepped behind Vale, using him for cover. But Kai’s face – what Irene could see of it – had grown cold at the sight of Catherine being carried along helpless. ‘How did they get hold of her?’ he demanded under his breath. ‘She was safe with Columbine.’

Fury knotted in Irene’s stomach and she glared at Shan Yuan, locking her hand around his wrist as he began to inch away. ‘Catherine is here because she wanted to help. Unwise, but she had good intentions. Vale, will claims of kidnapping be any use here?’

‘This is almost certainly an attempt to draw us out, and that would expose us to whatever they have planned. So would any attempt to rescue Catherine.’ Vale’s expression was grim, and Kai was nodding.

‘Agreed.’ If sheer force of will could kill, Irene’s thoughts would have bored a hole in the back of Lord Guantes’ head. Unfortunately, she couldn’t manage that – but there were other things she could try. ‘But I can black the whole place out, which will give us a fighting chance at breaking her out. I can’t turn the lights off from here, though – the Language would never be heard over the noise of that crowd. I’ll get to the generators and turn the electricity off at source. If you wait in the theatre, you can grab Catherine in the chaos.’

‘What about Lord Guantes?’

‘At the moment, I’m more worried about Catherine.’ How many times had Irene risked herself to get information? Of course Catherine would run off and do the very same thing. For the first time in a long while, she felt a degree of sympathy for her parents. ‘If you can grab Lord Guantes as well, then by all means do so.’

‘Am I to have no say in this operation?’ Shan Yuan demanded.

‘You are at perfect liberty to walk away,’ Irene said through gritted teeth, ‘but given that Catherine helped you get in here, I’d hope you’d feel some responsibility for her predicament.’

Shan Yuan opened his mouth, then shut it again. Perhaps he was considering the political optics. What would it do to his career if he was held responsible for losing an important Fae’s niece – who also happened to be a Librarian’s apprentice? Or perhaps he was considering Kai’s opinion of him. After all, Kai was staring at him, wearing an expression of hope that his brother would do the right thing.

‘Be careful, Winters,’ Vale warned her. ‘I cannot shake the feeling that we’ve missed something important.’

‘There’s one obvious thing we’re missing. Lady Guantes isn’t here.’ She turned to view the throng of people around them – picturing them as a deck of cards, scattered face down on a table. Any one of them could turn out to be the deadly Queen of Spades. ‘She may already be in the theatre. Watch out for her.’

‘One of us should come with you—’ Kai started.

‘Three of you have a decent chance of getting Catherine to safety in the darkness, against Guantes’ minions,’ Irene said regretfully, ‘but it would be harder for two of you. I’ll take all precautions.’ She touched Kai’s hand for a moment, a reassurance to them both, then dived back into the crowd.

The architects had positioned the electrical generators on the top floor, away from the public areas. Fortunately Columbine had been able to provide plans of the building earlier, which meant that Irene knew roughly where she was going.

The upper levels of the building were formed of sturdy brick, rather than the elegant stone and tile of the areas beneath. The rooms here were oddly shaped, built to fit around the large glass dome which crowned the nave below. The building had only been open for a couple of weeks, so these rooms and corridors still looked new and sharp edged, without the distractions of the crowd. Under the harsh ether-lights which provided illumination, occasional numbers or words were scrawled on the whitewashed walls. These indicated which rooms were for storage or machinery – and which held the generators. But there was an obstacle, of course.

‘Excuse me, ma’am.’ Two men were guarding the generator room. Irene thought it was a sensible precaution, given the over-enthusiastic men and woman of science gathered below. Some would just love the chance to ‘improve’ the building’s power supply. ‘This area’s out of bounds.’

Irene slipped a Secret Service identification card out of her handbag and displayed it. (Really, she was going to owe Columbine a lot of favours after tonight.) ‘Government business,’ she said. ‘We’re checking for saboteurs.’

He peered at it, frowning. ‘Sorry, ma’am. It’s been one of those nights. Will you need any assistance?’

‘If you’ll just unlock the door for me, please.’

He opened the door and switched on the light – and the sound hit her like a blow as she stepped inside. The room was huge, larger than it had seemed on the building’s plans. Wheels twice her height spun in constant rotation, half-sunk into the floor. These were paired with and connected to smaller wheels on the same axles. Heavy cables led everywhere – upwards to what looked like windmills which could be folded out onto the roof. They also led downwards through the floor and everywhere she tried to step, in a maze of connections. The air was harsh with the smells of oil, gasoline and iron – a sharp contrast to the perfumed guests and floral displays in the rooms below. The place seemed to pulse like a mechanical heart, and for a moment Irene was uncertain of her plan. She was staggered by the noise and complexity of the place.

But a moment of doubt was all she would allow herself. She took a deep breath and raised her voice above the ambient volume. ‘Electrical generators, shut down safely and stop transmitting power!’

The words hung in the air – and then it all went wrong.

It was as if her use of the Language had triggered some kind of paralysis. She couldn’t move. She couldn’t breathe. Dust motes glinted in the air as they spun downwards, and they fell slowly, so slowly, and the world itself shifted perspective around her. Her surroundings changed from a sharply lit room full of machinery, to a dimly lit twilight where silently turning wheels gently spun to a halt. Beneath her feet, a circle of light blinked into existence. Despite her frozen state, she could see it was edged with and ornamented by words in the Language that gleamed in the shadows.

And opposite her, barely a few yards away, a figure unfolded itself. It was as though it slipped sideways, through a line drawn in mid-air, to emerge into three dimensions. He was robed in black, like a Benedictine monk – or some other, darker order. But when he raised his hands to push his hood back, Irene recognized his face.

Irene could breathe again now, but horror and sheer terror made her throat dry. ‘Alberich,’ she whispered.

She’d seen this particular face once before, in a burning library. He could wear multiple faces and change his skin, so she wondered why he was attached to this one. Was it his true aspect, or had he left that far behind? There was nothing about his appearance to declare him a relentless traitor and the Library’s greatest enemy. She noted the receding hairline, thin eyebrows, strong nose and jaw, deep-set eyes, lean shoulders and rope-sandalled feet – quite ordinary-looking, in fact. But she associated this face with unrelenting malice and eternal darkness. She quite simply could not look at him and see a normal man – not when she knew what he was.