‘In which case we might have to wake Al Ahiz up and induce him to tell us where he’s put it.’

‘Can we just stick to simple stealing?’

‘You’re right.’ He plucked one of his light-bees out of the air and dropped it in Alessandra’s palm. ‘Start moving some of these around. There could be a hidey-hole. I’m going upstairs.’

‘Be careful.’ She held the bee up, and it fluttered about, getting its bearings.

Benzamir tiptoed to the door, listened carefully and tried the latch. It was only then that he noticed the ingenious lock. ‘Amazing,’ he said, testing the strength of the iron rods that slotted into the door frame. ‘If I wasn’t on this side of the door, and I couldn’t just slice through the hinges with a laser, I’d be completely baffled.’

He gripped the lock mechanism in both hands and heaved it through a quarter turn. The bolts slid out of the frame with a well-oiled click. He tried the latch again, and the door swung open.

The light behind him faded to nothing. He was in a corridor that was dark to normal vision, but not to his; the cool night air made blue streamers where it seeped in around the high window, and the door that led to the courtyard was outlined in azure. A couple of cats prowled in from another room, disturbed by the noise. At least, Benzamir hoped they were cats. It was difficult to tell just from the heat bloom, though they moved with a casual feline assurance.

He knelt down, let them sniff him and butt their sleek heads against his hand. He scratched each one between the ears, then shooed them gently away. He glanced through to where they had come from: a kitchen, with the embers of the evening’s fire still warm in the hearth. Time to try upstairs.

Al Ahiz lived alone. His neighbours had joked, even as they watched a detachment of Ethiopian soldiers turn the collector’s house upside down, that he had no need for the company of people: his many books were his many wives. And Benzamir, standing in the crowd with Wahir, Said and Alessandra, had watched as Al Ahiz simultaneously protested his innocence in the affair of the metal User book and urged great caution over the way rough warrior fingers abused his fragile pages.

Benzamir reached the landing and stopped to listen. Loud snores emanated from one room. The two others were locked, but not for long. They contained nothing but books. The Ethiopians had been in the house from dawn till mid-afternoon. Clearly, what they were looking for wasn’t in plain sight, its metal spine turned outwards on one of the shelves groaning with age and knowledge.

Benzamir thought it a crime that any book be held a prisoner. Al Ahiz was guilty of a far greater offence than handling the emperor of Kenya’s property: those books, sitting unopened, useless, rotting, represented an information abyss, a word hell. He shuddered, closed the doors again and sneaked into Al Ahiz’s bedroom.

He lay on his bed, shrouded by net, like a great white whale caught by a fisherman. Yet more books were mixed in with his few personal items. The light-bee selectively lit up some of the titles, written by long dead hands in long forgotten languages. Benzamir wondered if Al Ahiz even knew what he had.

Resisting the urge to chant from the Necronomicon and translate the mystic symbols of Voynich, he checked the walls, floor and ceiling in infra-red for any telltale signs of hidden doors and secret voids.

Al Ahiz turned over, grunted, and continued sleeping. His snoring diminished to a soft suspiration.

Benzamir was at a loss. The Ethiopians had had hours to search, and had turned up nothing. Without a doubt they would have questioned the collector closely, and might have resorted to a little rough handling when the book didn’t turn up. Either soft, blubbery Al Ahiz was as hard as nails, or he genuinely didn’t have the book.

Where hadn’t the soldiers looked? More importantly, where wouldn’t they look? If there were no hiding places built into the house, where would someone hide something of immense value?

He stalked around the room again, increasingly frustrated. All it would need was for the nightwatch, or a stray Ethiopian patrol, to come across Said, or for Al Ahiz to answer the call of nature, and the game would be up. He was putting them all in danger.

On Al Ahiz’s table was a pile of outsized books, enormous tomes meant for show and public reading: a Qur’an, a Capital, and a Bible, sitting together. One at a time he carried them out of the bedroom and put them on the floor.

He pulled the bedroom door to and brightened his light-bee.

The Qur’an was an exquisite work of illumination and calligraphy, compared with the prosaic Cyrillic of the Capital. Both books were post-Turn, painstakingly copied by hand by scholar or holy man. The Bible had a heavy tooled leather and wood cover, a gilded cross supported by an ox, an eagle, a lion and a man. The clasp that held it shut was fastened by a little brass lock.

‘This is the one,’ said Benzamir, and faithfully carried the other two books back into the bedroom. Al Ahiz was now on his vast stomach, snorting into his pillow.

Benzamir heaved the Bible up; it was a heavy, cumbersome thing, to be processed and venerated, not carried under one arm or slipped into a bag. He staggered downstairs with it and backed into the first library, where Alessandra was still scooping books off the shelves and tapping behind on the woodwork.

‘What’s that?’ she asked.

‘I think it’s what everyone in this city is looking for.’ He laid it down on the floor and inspected the lock. ‘I could pick it, but I don’t have a bent piece of wire of the right gauge.’

He pressed the mouth of his laser against it and gave it the most perfunctory of pulses. Shiny metal slithered into the cracks between the stone flags, leaving a thin smoke trail of burned dust as it flowed.

‘Ready?’ he said, and flicked the remains of the clasp away. ‘Normally, I wouldn’t dream of wrecking such a beautiful piece of work, but I have a feeling someone’s beaten me to it.’

He opened the cover, and Alessandra crowded close. Her fingers turned the pages over one by one: title page, a list of the books of the Bible, Genesis Chapter One. ‘What language is this?’

‘Greek. It’s post-Turn, but it’s an ancient translation. A shame, really . . .’ He leaned forward, gathered enough of the unopened pages to take in half of Numbers, and drew them back.

Al Ahiz had cut out the centre of the Bible, leaving a rectangular space big enough for the User book. Everything from Balaam’s donkey to the Damascus Road had been excised.

Alessandra lifted the User book free. ‘This is it. How did you ever find it?’

‘Luck and intuition. Maybe even magic.’ Benzamir closed the Bible and left it on the floor for Al Ahiz to find in the morning.

‘And really?’

‘The Ethiopians are Copts. They’d never have imagined for one moment that a man would have cut up the Scriptures, let alone one as rich in history as this. It must have broken Al Ahiz’s heart to do it: his loss, our gain.’

Alessandra put the book on the rug that had covered the trapdoor and wrapped it up carefully. ‘Can we go now?’

‘Do you think we’ve left Wahir and Said outside long enough yet? Shouldn’t we leave it a little longer, so that their relief at our reappearance is all the greater?’

‘That’d be a terrible thing to do. Wizard or no, get down those steps.’ Alessandra handed Benzamir the book. ‘And you can get rid of this damn glowing insect. It’s just too strange.’

Her light-bee sailed across and joined his, and immediately she stumbled over the Bible.

‘Don’t reject something just because it seems strange. It’s comfort that will kill you in the end.’ Benzamir clutched the book to his chest and carefully descended into the cellar. Alessandra picked herself up and followed the fading light.