There was a patronising tone to her reply. ‘The ascent of civilisation in Greece and Rome, the rise of Christianity, the Old World discovering the New, and then through to the present day. Enough for people to see where mistakes were made, and correct them next time.’

‘Damn, I’m glad you weren’t my history teacher,’ said Nina in disdain. ‘What about, well, the rest of the entire world? The Egyptians? The Chinese? The Aztecs and Mayans and the other pre-Columbian civilisations? What about the rise of Islam? That’s had kind of an influence on events for the past fourteen hundred years.’

Eleanor scowled. ‘None of that is important.’

‘Who are you to decide what’s important?’

‘The person who built the library! I’m the one preserving knowledge for the future.’

‘No, you’re censoring it. The things you decide are worthless could be of huge value to someone else. If you were really concerned about preserving knowledge, you’d put everything you could in there. Not just dry technical stuff; where’s the art, or literature? Music, movies, everyday culture?’

The old woman stopped the wheelchair. ‘Are you suggesting I should preserve every trashy paperback novel? Every obscenity-filled rap song? Every self-aggrandising selfie and internet comment?’

‘If you can, why not?’

The proposal genuinely angered Eleanor. ‘That would be a signal-to-noise ratio so poor, the garbage would drown out everything of value!’

‘That “garbage” might tell someone in the future more about our society than any list of kings and queens.’

‘Liberal nonsense,’ she spat, setting off again. ‘Exactly the kind of weak, woolly thinking that’s accelerating the collapse, giving equal weight to all sides. It’s probably for the best that the end comes quickly, so people have to focus on what’s important!’ She reached a set of doors, impatiently waving for Broates to open them. ‘Now, in here.’

Nina followed her in. The room appeared to be a workshop or laboratory. Doors led off to each side, but Eleanor headed to one opposite: a gleaming metal vault. ‘This, Professor Wilde,’ she said, anger replaced by triumph, ‘is where I will sit out the fall of civilisation.’

There was another palm-print reader on a console before the oversized entrance. She placed her hand upon it. The door slowly slid open with a low growl of motors. Beyond, another large room was revealed, the concrete walls reinforced by steel beams. ‘Here he is,’ she proclaimed, going to the object at the vault’s centre: the stolen sarcophagus. ‘The last of the Nephilim.’

Nina stopped in shock. ‘The . . . the Nephilim?’

‘You know what they are?’

‘Of course I do! “There were giants in the world in those days” – from the Book of Genesis.’

‘Chapter six, verse four,’ Eleanor said with a nod. ‘“When the sons of God came in unto the daughters of men, and they bore children to them.”’