‘Because it happens to us all, sooner or later, doesn’t it? Every day of my working life, I have walked to work up Sarum Street, and come by this place, so dark and unfriendly. I never pass it without a shudder. It is mortality. It is the fate that awaits us all should we cross the line. Do you think it was easy coming here today? No, sir. It has taken me a week to find the confidence. This afternoon, as I raised my hand to rap at the door, my courage almost fled. But I am a true citizen of Imperial Hesperus. I am a true son of the Emperor. It was my duty to report this, no matter what fate awaits me.’

The officer nodded. The clock ticked.

‘Tell me what you understand by “the Number of Ruin”,’ said the officer.

Master Imus sat back and shrugged. ‘It is an impossible number, an abomination. It is a notation of filthy power. Numbers own power, you see. My father raised me to respect three and seven, thirteen and the triple sixes, the primes, the constants. But the Number of Ruin, that is the number of–’

‘Of?’

‘Of the warp,’ Imus whispered, looking to one side and then the other as if in fear of being overheard.

The officer nodded his head. ‘So Hapshant has taught me. Can you show me the number? Can you write it down?’

‘Are you mad?’

‘This room is warded and I am armed. Can you show me the number?’ Master Imus took a data-slate from his robe pocket. It was battered and worn from use. He activated it and entered a series of digits into the display.

‘There are the accounts,’ he said, pausing before handing the slate over. ‘I have selected the key section. Please be careful.’

The officer held out his hand. ‘Show it to me, please, sir.’

Master Imus hesitated. ‘What did you say your name was, young man?’ ‘Eisenhorn,’ the officer replied. ‘Interrogator Eisenhorn of the Emperor’s Holy Ordos. Why?’

‘Please, please be careful with this, Interrogator Eisenhorn.’

Master Imus handed the old data-slate to the officer. The officer looked at the screen with a slight frown.

The gilt clock stopped ticking. A strange silence filled the room.

‘I–’ the officer began to say, and caught fire. Blue flames, as hot as a burner torch, consumed his skin and roasted the flesh off his bones until nothing remained except dripping, blackened meat and a charred skull wrenched into a rictus by heat-tightened sinews. The data-slate dropped onto the desk from a smoking, skeletal hand with a thump. The officer’s clothing was untouched.

The flames guttered out and the scorched corpse slumped forwards with a crack of dry ligaments. Imus got up and backed away. His eyes were wide. He fought back a terrible desire to urinate.