‘The tracker!’ Cheng said excitedly. ‘It has a wireless connection to the computers at the research centre. Everything it does is recorded – so there’ll be a copy of whatever Gadreel saw!’

‘Then we’ve got to get back there,’ said Nina. ‘Fast.’ She looked around as Hui’s helicopter came in to land, ready to ferry them to the base.

The vimana-kal’s interior was overcrowded beyond the point of mere discomfort, but all those aboard knew they would have to endure it. They had greater concerns.

Sidona had made Zan connect the tracker to the craft’s crystal heart. Even though it was much smaller than its counterpart in the crippled fortress, she soon discovered the machine gave her every bit as much power and control over the earth’s energies. Her first priority had been to locate Tartarus, guiding their craft towards it.

Next came vengeance.

‘The beasts cannot be allowed to claim the vimana,’ Gadreel growled. ‘We must destroy it to keep it from them.’

‘My lord,’ Sidona said quietly, ‘the warriors who remained with it . . .’

He closed his eyes. ‘I know.’ A breath, then he opened them again, his expression stone. ‘They will not be forgotten.’ The other Nephilim crushed together in the cabin expressed silent appreciation for their sacrifice. ‘Now. Begin.’

Sidona bowed her head, then turned to Zan. ‘The vimana. Show it to me.’

‘Yes, my lady,’ the translator replied nervously. He zoomed the laptop’s map in on Xinengyuan. ‘It is here.’

‘Target it,’ ordered Gadreel. Zan hesitantly did so, the crosshairs locking on the park. ‘What you did to the tower,’ the Nephilim leader continued to his wife, ‘do so again. Except . . . how great a devastation can you bring?’

‘I do not know,’ she replied. Her face hardened. ‘But for Turel, for all our people who died at the hands of the beasts, I will find out.’

She closed her eyes, then touched her hands to the qi tracker’s core – and the vimana-kal’s crystal heart.

The helicopter landed. Major Wu sprinted to it, vaulting through the hatch and crouching behind the pilot. ‘It went south!’ she shouted as the Z-20 took off again. ‘Get after it, full speed!’

The aircraft came about, the city dropping away. ‘There!’ said the co-pilot, pointing. A golden dot was visible in the sky.

‘It’s a long way ahead,’ the pilot warned.

‘Follow it,’ Wu snapped, hiding her worry. The smaller UFO was travelling at the speed of a plane rather than a helicopter. But if it had the same radar immunity as its parent, she couldn’t allow it to be lost to sight.

The Z-20 picked up speed, Xinengyuan sweeping past below. But it became clear after a couple of minutes that her quarry was outpacing her. The dot shrank, becoming fainter. She cursed—