‘But what do we do when—’ Kai started.

‘We’ll work out the details when we’ve caught the accomplice,’ Irene said firmly. ‘Let’s do this in manageable stages. Are you ready?’

‘The sooner, the better,’ Kai said. He was still as tense as a stretched wire, his shoulders hunched and his expression guarded. Irene silently scolded herself as she became aware of at least part of the problem. He’d been imprisoned only a few months back, depending on others to rescue him. It was hardly surprising if being chained in a cell again left him on edge.

‘Right.’ She stood up, and he followed. ‘Shackles, unlock and fall off.’

The shackles were human magic, not Fae or dragon work, and they yielded to the Language like any other piece of mortal metalwork – falling to the ground in a clash of metal.

Irene stepped to one side of the door, leaving the path clear for Kai. ‘Door, unlock. Wards on door and entrance, fall. Door, open.’

Her head throbbed with the newly returned headache, which had apparently only left for a brief holiday. It had now come back with its friends to stay. But at least there was a convenient stone wall to lean on. She did that for a moment, while Kai exploded through the just-opened door and ‘reasoned’ with the guards on the other side. They didn’t even have time to level their crossbows.

When she followed him out into the guardroom, everyone was unconscious. This included a robed man, who was presumably the mage unfortunate enough to have been posted on guard duty. ‘A bit wholesale,’ she said mildly.

Kai shrugged. ‘None of them are dead. Besides, we don’t want them raising the alarm earlier than necessary.’

‘True,’ Irene admitted. She tugged at the mage’s heavy over-robes. ‘Give me a hand with these, please.’

Kai frowned for a moment, then looked at her bedraggled, bloodstained ballgown and nodded. When Irene had donned them she still looked badly dressed, but at least she might be a little less conspicuous.

‘The Neva river is that way,’ Kai said, pointing helpfully down the corridor.

Irene led the way, stalking along in a business-like manner and hoping that anyone they ran into would look at the robes and not at her face. Her personal worries drew her face into a scowl, and she saw no reason to attempt a smile. There was the threat to the Library. There was Alberich, who was an ongoing terror just as much as a current danger. There were all her friends and family who were in danger. And there was Zayanna who, barring a miracle and a very implausible explanation, had lied to her.

She’d liked Zayanna.

From the distance came the sound of running feet and a clanging bell. They were several corridors away from the cells by now, in a direction that Irene would have described as hopelessly lost, but which Kai claimed led straight towards the river. These passages, deep beneath the Winter Palace, were far from the glorious corridors of the upper levels – or even the prosaic but business-like archives beneath the cathedral. They were floored with flagstones, and walled with granite, clean but old. These passageways were cold with the deep bone-chill of freezing water seeping through earth and stone. Even the air felt damp.

‘The hunt’s up,’ Kai said concisely and obviously.

‘We knew it would be,’ Irene agreed. ‘Is it much further?’

‘A bit. I’m assuming that you want to get as close as possible?’

‘Right. The less wall and foundation I have to remove, the easier it’ll be.’

‘How are we leaving this world, after that?’

‘Through the closest library to the Library itself.’ She caught Kai’s frown. ‘I know it might be faster in some ways for you to carry us out as a dragon, but I need to leave word at the Library as soon as possible. If something does go wrong when we try to catch Zayanna, I don’t want to be the idiot who didn’t tell anyone where we were going or what we were up to—’

She came to a dead stop as a roar echoed through the passages. Panicked back-brain instinct urged her to cower and hide, or to look for a nice high tree to climb. ‘What the hell is that?’ she hissed.

‘The Empress’ tigers. But I don’t think they’re nearby.’ Kai kept on walking, far more casual about the noise than she was, and Irene had to hurry to catch up.

‘You mean those big white Siberian—’

‘They’d have to be Bengal tigers,’ Kai said seriously. ‘You only get white tigers from Bengal. My uncle gets quite annoyed about it. His subject kingdoms often send him furs as tribute, but Siberian tigers are always orange, never white. He once said—’

‘The operative word is big,’ Irene cut in. ‘How good are tigers at tracking by scent?’

‘Well, hounds are better for coursing game,’ Kai began. Then he caught Irene’s glare. ‘Quite good,’ he said meekly. ‘I’ve never tried training them.’

‘I don’t suppose they’ll go to their knees and worship you, the way that bear did?’

‘Probably not,’ Kai said regretfully. Another roar split the air, closer now. ‘They’re cats, after all.’

Irene wished that the Undying Empress had preferred bears as pets.

‘This is about as close as we’re going to get.’ Kai stopped at a bend in the passage and laid his hand against the wall. ‘I can feel the flowing water some yards beyond this. They laid the foundations well.’