‘They ain’t up to much,’ said Lewis. ‘Take ’em down!’ And he and his fighters steamed into the pack, lashing out with spears and clubs. At the same time Big Mick and his crew circled round the dinosaur and hit them from the rear. The sight of reinforcements gave the defending kids fresh hope and it took them less than a minute to hack the grown-ups to the floor.

Maxie had noticed a kid who seemed to be leading the locals. At first she’d thought it was a boy, but as she got closer she realized that she was mistaken.

‘You in charge here?’ Maxie asked her. The girl looked around at the other kids with her and shrugged.

‘I suppose I am.’

‘What’s your name?’

‘Jackson.’

‘Well, Jackson, do you want to tell us what’s going on?’

‘Who are you?’ Jackson said warily.

‘It’s all right, they’re with me.’ Brooke stepped forward. Jackson looked first shocked then delighted.

‘Brooke … We thought you were dead.’ Jackson gave her a quick hug. ‘Are the others with you?’

Maxie remembered rescuing Brooke. The mangled bodies of her friends lying in the road.

Brooke didn’t reply. She didn’t have to. Her face said it all. Jackson swore and spat on one of the dead grown-ups.

‘I don’t get it,’ said Brooke. ‘What’s happened here?’

‘I don’t really know, to tell you the truth,’ said Jackson. ‘It’s been mad. No time to stop and think. Far as we can tell, the sickos have got in from downstairs; they somehow got past the locked doors. The museum’s full of them. They’re all over the place.’

‘Where’s everyone else?’ said Brooke.

‘It’s OK. They’re mostly safe. They’re up in the minerals gallery.’

‘Mostly?’

‘I don’t know.’ Jackson peered into the darkness. She looked tired. ‘I think we might have lost some. I can’t keep up with what’s happening.’

Maxie had a chilly feeling of unease. It wasn’t just the grown-ups. There was something else. That shiver that had run through her outside. She bent her neck back and craned up at the looming black skeleton of the diplodocus.

She remembered now what had happened when she’d come here the first time with her mum and dad – the dinosaurs. They’d totally freaked her out. She must only have been about four or five years old. There had been some kind of moving exhibit, with life-size animatronic dinosaurs, and she’d had nightmares for weeks. She still found dinosaurs a bit creepy. It was the teeth that did it. Maxie didn’t like teeth.

She switched her attention to the dead bodies on the floor, crouching down to try and identify them. They’d been chopped up pretty badly.

‘Any of this lot yours?’ she asked Jackson.

‘No. All sickos.’

Maxie gave her a questioning look.

‘It’s what we call grown-ups,’ Brooke explained.