‘A shield? What is this, Star Trek? No, more like Independence Day,’ Eddie corrected. ‘But we still need to land! Tell him to get on that roof!’

Cheng did so, but the pilot was already gaining height. The two fangs tried to follow, only to be blocked by the hull above them. The minigun kept up its assault, hosing the fortress with fire. The gunner cried out in excitement. Eddie looked back. The flashes around the dragon’s eyes weakened, and debris flew into the air. Then he lost sight of it as the helicopter turned.

The skyscraper’s roof came into view; it did indeed have a helipad. The Z-20 slowed for a landing, but the pilot was now battling to maintain control, red lights flashing on his instrument panel. He extended the landing gear. ‘Macy, hang on!’ Eddie said, taking hold of her. Just a few more seconds . . .

A new noise reached Nina: the thud of rotor blades. She looked around, but couldn’t see the helicopter past the buildings.

She saw the fortress, though. The shimmering dragon had dropped off warriors to pursue her on the ground, but was now airborne again – and once it spotted her, it would direct them to their target.

The construction site came into view as she rounded a bend, a dozen unfinished apartment blocks rising into the sky. A girder swung wildly from a tower crane. Its operator had seen the sinister UFO approaching and abandoned his post. Dozens more men in hard hats scurried in panic at ground level.

If she led the Nephilim to the site, innocent people would die. She had to find somewhere else.

Tiring, lungs aching, she reached a crossroads. Going right, northwards, looked too open; those aboard the fortress would spot her with ease. Left would take her towards the city’s centre, where there were likely to be more people – but there were also more buildings, more cover. And everything had the almost fake, movie-set appearance of newly constructed properties. No goods in the store windows, no curtains in the apartments, no cars on the street.

Nobody to get hurt. She went left, quickly reaching the cover of another building—

The helicopter suddenly grew louder.

She looked up as it clattered overhead. It was in trouble, struggling to hold course. The Nephilim attack had caused damage – she saw something break loose from the fuselage and spin down towards the ground. It was not going down without a fight, though. Tracer fire blazed back at its attacker. The aircraft headed towards the city centre, disappearing behind an apartment block.

Nina ran after it. The fortress was not yet in sight behind her. Another intersection ahead – another chance to throw off the hunters. Keep going—

A siren’s rising wail reached her. Maybe she was about to get some support . . .

A shout from behind.