He shook his head, eager to correct her. ‘No, no. The Hindus took the word from the Nephilim! It can also mean “flying palace” or “flying castle” – and the Turkish vault was one of them. The Atlanteans somehow flew it to Gobekli Tepe. The fortress we found in the iceberg might have got there the same way.’

‘So it really was a UFO?’ Eddie said dubiously. ‘As in, literally an unidentified flying object?’

Nina looked back at the vault, seeing it in a new light. ‘We have seen things levitated by earth energy,’ she said. ‘Big things, like the Sky Stone. That was the size of a house.’

‘The Sky Stone?’ Hui asked.

‘A meteorite found by the Atlanteans. Earth energy let it levitate against the planet’s magnetic field. Certain people, Atlantean priestesses, could also use it to channel and direct huge bolts of earth energy. They intended to use it as a weapon, but it went catastrophically wrong.’

‘How so?’ said Cheng.

‘Remember how Atlantis dropped into the sea?’ Eddie told him. ‘There you go.’

‘That’s what you get when you try to turn things you don’t understand into superweapons,’ said Nina. ‘Hard to think of a bigger example of hubris. Although people keep trying to beat it.’ She gave her hosts a pointed look.

Wu merely frowned in return. Hui, on the other hand, became defensive. ‘This technology has far more uses than weapons! It is a non-polluting source of power. No more coal, no more oil, no more nuclear. That is why we are so determined to unlock the past – to build a new future.’

‘With China controlling the technology, of course.’

‘If America had it, they would do nothing different. Nor would Britain,’ Hui added to Eddie.

The Yorkshireman snorted. ‘If we had it, I guarantee we’d hand most of it straight over to the Yanks in exchange for a better trade deal on haggis and strong cheese, then privatise the rest and flog it off for a tenth of what it was worth.’

‘This technology can change the world,’ Hui insisted. ‘If we can make it work. Professor Wilde, please hear us out. I am sure we will be able to convince you to help us. Not only for China, but for the rest of the planet.’

Nina did not answer, instead turning at someone’s approach: Colonel Wu, accompanied by two soldiers. He spoke to Hui and his daughter in Mandarin, then issued a command.

‘Come this way, please,’ said Hui, starting for an exit.

‘Where are we going?’ Nina asked.

‘To see the sarcophagus. To meet our . . . guest.’

‘That doesn’t sound ominous or anything,’ rumbled Eddie as they followed.