‘A man just like him,’ said Eisenhorn. ‘No, that’s wrong. More than him. Goran Gobleka is a hired killer with aspirations above his abilities. He found someone like the people he serves. Lilean Chase. The King in Yellow.’

He looked at Endor.

‘Could yellow mean flames, do you think?’ he asked. ‘A figure burning from head to foot? On fire entirely? A symbolic name for someone who has burned through and been transmuted? All that they thought they were, torched away, and only the truth left standing?’

‘Gregor,’ said Endor. ‘I want to say, just me to you, I have no bloody idea what you’re on about.’

Eisenhorn looked at him, hopelessly. He tried to put it into words, easy words, but no words would come out. Only strangled un-word noises. Endor looked puzzled for a moment, then his eyes slowly gave way, and small worms started to writhe and slide down his cheeks. He stood where he was, frozen.

The chirring of the insects grew into a roar, a strident loud, slow click beating time to their din, the mechanism of a clock beating out the seconds.

‘It’s almost time,’ said Ravenor.

Eisenhorn looked up. He was standing in shadow. The huge arch of the Spatian Gate was above him. The chirring of the insects was the roar of the crowds lining the eighteen-kilometre route of the Avenue Victor Bellum. Two billion cheering voices. He could hear the marching bands of the procession approaching, the grumble of the war machines, the thump-step of the Titan engines. He could feel the monumental noise vibrating his diaphragm.

This was Thracian, Hive Primaris. The Day of the Great Triumph. Ravenor was dressed in his finest raiment, his Inquisitorial rosette on his breast, just above the small tribe badge of Clan Esw Sweydyr.

The Spatian Gate was made of gleaming white ethercite, and it was so tall the great Titans could march beneath its span. Ravenor looked up at it. He seemed so young and invulnerable.

‘This is it,’ he said, smiling. ‘Just seconds now. The moment of transformation.’

He looked at Eisenhorn.

‘Mine,’ he said, ‘most particularly. But yours too. This moment changes you. You were always driven Gregor, but what happens here today – what happens to me – it propels you on from this point. With a fury, a rage you never lose. It sets you on the path into the dark places, and from here, there is no turning back for you.

‘Even though I try,’ he added. ‘I try my damnedest. You know what they will make me do, don’t you?’

‘Hunt for me.’

‘Hunt for you. Hunt you down as a heretic. It will take years, Gregor. It will cost us both. And then, at last, we will stand face-to-face in the King’s City of Dust, and it will end.’

‘How will it end, Gideon?’ Eisenhorn asked.

‘Oh, how do you think?’ replied Ravenor. ‘The pupil always outstrips the master.’