‘Yes. Many undying escaped the Coalition invasion, and fled further. A flock of generation starships rose from the ice of Port Sol, even as the Coalition ships approached, commanded by undying; nobody knows what became of them. But while they were here, you see, the undying perturbed the gene pool, with their own taint of longevity. It’s not a surprise that throwbacks like you, as the Commission calls you, should arise here.’

‘Luru Parz, I don’t know what to do. Will I have to hide?’

‘Yes. But you mustn’t be ashamed. There is an evolutionary logic to our longevity.’ Luru clutched a fist over her heart. ‘Listen to me. Before we were human, when we were animals, we died after the end of our fertile years, like animals. But then, as we evolved, we changed. We lived on, long after fertility ended. Do you know why? So that grandmothers could help their daughters raise the next generation. And that is how we overcame the other animals, and came to own the Earth - through longevity. Immortality is good for the species, even if the species doesn’t know it. You must hide, Faya. But you must not be ashamed of what you are.’

‘I don’t want to hide.’

‘You don’t have a choice. The Coalition are planning a new future for mankind, an expansion to the stars that will sweep on, for ever. There will be no place for the old. But of course that’s just the latest rationalisation. People have always burned witches.’

Faya didn’t know what a witch was.

And then a Virtual of Faya’s mother’s face congealed in the air before her, the bearer of bad news about Lieta.

Faya and Spina held each other, sitting side by side. For now they were done with weeping, and they had readmitted Ank Sool, the Commissary.

‘I don’t understand,’ Faya said. It was the brevity that was impossible to bear - a handful of Dances, a flash of beauty and joy, and then dust. And why should her sister die so suddenly now, why was her life cut short, just as the prospect of eternity opened up for Faya? ‘Why Lieta? Why now?’

Sool said, ‘Blame the Qax. The pharaohs never bred true. Many of their offspring died young, or their development stopped at an unsuitable age, so that immortality remained in the gift of the occupiers. The Qax were always in control, you see.’

Faya said carefully, ‘Commissary, I think I will always suspect, in a corner of my heart, that you allowed this death to happen, in order to bring me under control.’

His eyes were blank. ‘The Commission for Historical Truth has no need of such devices.’

Spina grasped her daughter’s hands. ‘Take the mortality treatment, dear. It’s painless. Get it over, and you will be safe.’