Dritzehn clasped the mirror to his chest and murmured something indistinct. I waited for him to repeat it.

‘How can I be part of this enterprise?’

‘The housing and the mirrors will be manufactured separately. We need someone to polish the mirrors.’

‘I can do that.’ He furrowed his face. ‘But not as a servant. If I am to be part of this, it must be for a share of the profits.’

‘The profits will be very great,’ I agreed, almost as if it were cause for concern. ‘For that reason, this endeavour must be a close secret. If knowledge of our art spreads, there will be no advantage.’

‘I can keep the secret.’

I glanced at Drach, who played his part and looked doubtful.

‘I am sure of it,’ I said. ‘But we must keep the circle small – no more than half a dozen men. Half the profits will accrue to me and Kaspar, as the inventors of this art. It follows that any man who invests must buy at least a quarter share of the remainder.’

‘How much is that?’

‘Eighty gulden.’

Dritzehn was a merchant: he could do his sums. ‘Thirty-two thousand mirrors – you will sell for how much?’

‘Half a gulden.’

‘Sixteen thousand gulden. Half to you, eight thousand. A quarter of the remainder to me: two thousand.’

He whispered the number like a man who has beheld God. I knew how he felt. Even now, the magnitude of the project awed me.

‘Can this be true?

‘We have the art and – you behold – the ambition. All we want is capital.’

‘Nothing can go wrong,’ Drach assured him.

‘Is this what you have been concocting in my basement all these months?’

‘A part of it.’ I changed the subject. ‘But you must decide quickly. There are many others who would happily take your place.’

Dritzehn wiped his brow and stared into the fire. Kaspar looked as though he was about to say something, but I tapped him under the table to stay quiet.

‘I will take the share you offer.’

‘It cannot be yours until we have the money,’ Kaspar warned.

‘You can have fifty gulden tonight. The rest I will fetch tomorrow.’ He thought for a moment. ‘You will sign a contract that this is to be used only for the good of the enterprise?’

‘Of course. But I must have absolute control.’

Dritzehn went to a chest by the wall. He fetched paper, a writing box and a heavy bag that clinked when he set it on the table. I tried not to stare.

He uncorked the bottle of ink and dipped in the pen. In the firelight, the ink dripped off the nib like drops of gold.

The fire had burned low and the servants were asleep. Dritzehn ushered us downstairs to the door himself.

‘Be careful on your way home,’ he warned me. ‘It is not safe carrying bags of gold through the streets.’

‘Nothing will happen to it.’

We crossed the road and walked around the corner. At that hour the streets were almost empty – but not quite. Two men stood in the shadows under a baker’s sign. They stepped out to block our path as we approached. One was tall and stocky and leaned on a thick staff; the other short and thin.

‘Did he agree?’ Stoltz asked.

I handed over the bag Dritzehn had given me. Stoltz hefted it in his hands, then passed it to Karl. The one-armed man struggled to hold it and the staff at the same time.

‘It’s all there,’ I said.

‘If it isn’t, you will soon know.’

The two men disappeared down an alley. We watched them until they were out of sight.

‘Is that for the good of the enterprise?’ Drach asked.

My conscience was clear. ‘If it keeps me from having my legs broken, it is certainly for the good of the enterprise.’

Stoltz had been wrong about money. It was not like a plough or a pair of bellows, to be hired out and returned. It was water driving the mill of endeavour. It did not matter where it came from or where it went. So long as it kept flowing.

France

They abandoned the car in a car park. Nick left the windows open and the keys on the front seat. Hopefully someone would steal it before the authorities found it. Then they went to the rail station.

Nick slept most of the way to Strasbourg, clutching his hand across his chest where he had the book tucked under his coat. When he woke, he saw the day had got darker. Flakes of snow whirled past the windows, while the sky promised more to come. On the opposite seat he saw Emily watching him.

‘What time is it?’

‘Almost noon.’

A hunger pang ripped through his stomach. ‘I’m starving.’

Emily reached in her purse and pulled out a paper bag. ‘I got you a croissant.’

Nick ripped off the end and stuffed it in his mouth. It felt like he hadn’t eaten in a week. ‘You’re a godsend. I don’t suppose you’ve got a cup of coffee in there as well?’

Emily slid a paper cup across the table between them, together with a pile of sweeteners and creams. He emptied three of each into the cup and swirled it with a plastic spoon while he devoured the rest of the croissant.

‘Did you sleep at all?’

‘A little. I couldn’t stop thinking.’ She stared out the window. ‘Gillian must have known something we don’t.’

Nick waited for her to go on.

‘She found the bestiary, and the card inside it – either of which would be a major discovery. But she didn’t tell anyone, not even Atheldene.’

‘So he says,’ Nick interrupted.

She acknowledged the point. ‘Then she locked the card in a bank vault and the book in the deep freeze, and disappeared. I assume to look for the “other” bestiary. Why?’

Nick sipped his coffee and let Emily continue.

‘She knew something. Something that made the other book even more valuable than the one she had.’

‘What?’

Emily screwed up her face. ‘I don’t know. But she must have found it quickly. She was only in Paris for a day after she saw the book.’

‘The day she went out to see Vandevelde.’ Nick thought back to the physicist, his evasions, his eagerness to prove he had nothing to hide. He wanted to pull out the card again, to see what Gillian might have seen on it. In the train carriage, even half empty, he didn’t dare.

‘Whatever it is, someone’s excited about it,’ he said. ‘It’s unreal. The speed they turned up at the book warehouse – and before that at the library. But if they know all about the book, why are they chasing after us to find it?’

Emily looked out the window, where the snow flurries were gathering force. ‘Maybe they don’t want to find it at all. Maybe they want to make sure it stays hidden.’

Near Liège, Belgium

Brother Jerome pored over the desk and rubbed his bloodshot eyes. Seeing Emily again had left him with a splitting headache. He reached for the plastic jar that was never far from his desk and popped two pills. As a younger man he’d prided himself on keeping his body pure. A temple, a fortress of God. Now the temple lay in ruins: flooded with caffeine to keep him alert, sedatives so he could sleep, codeine for the headaches and some pills his doctor had given him for his heart. And some stronger drugs, powders that couldn’t be prescribed, for the memories.

He looked over the notes he’d written.

bestiary

nova forma scribendi

Armand, Comte de Lorraine (Strasbourg??)

A new form of writing. Emily had always had a brilliant mind, a sort of academic cunning that knew when to look deeper. But there were some things she didn’t know. That was what she’d recognised in him: a depth of experience without equal. It had been an intoxicating mix.

Why did you come here? Jerome asked for the hundredth time. He was pleased he had managed to stay so outwardly calm – a lifetime of religious self-discipline still had some hold – but it had been an immense effort. The feelings she still aroused, anger and longing.

Forget her. He tried to focus his thoughts on the book again. Another bestiary in a new form of writing, illustrated by the Master of the Playing Cards. It was incredible. The discredited theories and baseless speculations would turn out to be correct. And maybe other, deeper secrets that prudent men only whispered.