The guard, who had been listening, raised his gun, finger fumbling at the trigger. The big man slammed the barrel down just before the guard fired. The guard struggled, but the big man pulled the gun out of his hand and shoved the guard back.

‘She is death,’ gasped the guard. ‘She has killed us all.’

‘I can help,’ said Mersadie, as the man turned back to her. ‘I think I can save you, save us. But I need to get away from here. I need to–’

‘Reach the Praetorian,’ said the man. ‘How do you even begin to have a reason for that?’

‘Because I need to tell him something that may save everything that he is fighting for.’

The man looked at her; the guard had hauled himself to his feet.

He does not have any reason to believe me, she thought, and then a phrase he had used rose in her mind, clear and bright. ‘Throne’s grace…’

‘How could–’

‘Because I am carrying a message from a saint,’ she said. ‘From a friend. From someone called Euphrati Keeler.’

The man looked at her, mouth half-open, not blinking.

‘And you can help?’ he said, and she could see the hope rising behind the fear. ‘You can protect us?’

‘Maybe,’ she said. ‘But not if we die now.’

In the dry poetry of the void-born, this manner of disaster was called a fire cascade. One ship exploded, and the debris was catapulted out as shrapnel. The debris struck another ship in close proximity, which exploded in turn, and then its debris destroyed another, and another, the disaster leaping from one victim, to many, to countless multitudes in a few bounds. It was a rare event, the vast distances involved in void manoeuvres saw to that. But the ships navigating the approach channels around Uranus’ moon Oberon were very close to each other. So close that several catastrophes had already been avoided by the narrowest margins. When the first ship exploded, the fire cascade followed within moments.

Wreckage flew out on silent waves of flaming gas. Pieces of torn metal the size of tanks struck unshielded hulls and punched through. Fuel lines ruptured. Promethium met plasma and roared out, ripping and burning.

Hundreds died – gasping for breath as billows of fire stole the air from where they slept, or stood, or crouched in the arms of those they loved, seared to dust and ash in superheated infernos, tumbled into the vacuum. On and on the cascade ran, seeded from one explosion into another.

Thousands died – cut apart by shearing metal, shot through by grains of debris flung through hulls in hundred-metre-wide shot blasts.

Hundreds of thousands died – spinning over and over in the torn chunks of their ships.