‘No,’ said Amelia and she slowly shook her head. ‘It wasn’t that. It would have been easier to deal with if it had been. We’d have known what it was. And we had no idea. It was a peculiar disease, like nothing any of us had ever encountered before. It came from nowhere, appeared overnight in a fully virulent form. And it seemed choosy – the young were spared, anyone under the age of fifteen, and the very old.’

‘That’s news to me,’ said Kyle, shifting uneasily in his seat.

‘I’m not surprised,’ said Amelia. ‘When the world went to pieces, the old were vulnerable. No one to look after them, easy prey for looters and house invaders. Most were simply killed. In the fog of war it was hard to see what was going on.’

‘Maybe you’re right,’ said Kyle. ‘I had some grand-parents living in Wood Green. Lost touch with them when it all kicked off.’

‘You’re saying older people aren’t affected by the disease?’ Ed asked.

‘Yes. People in their late eighties and over do not seem to have been affected. Several of us here are over ninety, and three are over a hundred. It passed us by. Why?’

‘Do you know why?’ asked Lewis.

‘We had theories. Perhaps old people had some degree of natural immunity to it, from some past infection. But that didn’t explain why no young people got it. Perhaps it only bothered with people who were strong enough to carry it. But that would assume that the disease had a degree of intelligence. Which is impossible. Or so we thought. Ah, but I’m getting ahead of myself.’ She gave a stern look to Kyle which softened into a smile.

‘You interrupted me,’ she said. ‘Got me off the subject. An old schoolboy trick.’

‘Sorry.’

‘As I was saying,’ Amelia went on, ‘I worked for the government during the war, doing my patriotic bit, and after that I moved around. I worked in Germany for a period, and America. For a few years I was at the Courtauld Institute of Biochemistry at Middlesex Hospital. I was even on the Board of Health for a spell … Oh, you don’t need to know all this. Just listen to me! I’m a typical rambling old person, showing off how much I can still remember. Suffice to say, I spent my entire adult life researching diseases and the beautiful mysteries of the human body.

‘And thirty years ago I retired, although I remained on various boards and charities and health advisory committees. And I got old. And I thought my usefulness was over. Apart from looking after Dorothy here.’ She touched her sister’s hand and she smiled back at her.