Maxie’s team had got stuck. Weren’t sure what to do. They’d chased some grown-ups through the corridors of the museum, past a load of stuffed bears and lions and bats. And then they’d run straight into a second, larger group that were coming the other way. In the chaos and near-panic, she’d ordered her kids through a big door into another gallery where they were now bottled up in the tight spaces between exhibits, unable to get back to the door.

Their madly slashing torch beams lit up a surreal fleet of creatures dangling from the ceiling: dolphins, sharks, killer whales, whale skeletons and, right in the middle, a gigantic life-sized model of a blue whale that dwarfed the stuffed elephants standing beneath it.

Her numbers were down. Most of the museum kids in her group had run off. She was left with Big Mick’s fighting force and just two of the locals. She had no idea how many mothers and fathers were in here, scrambling and hissing among the exhibits. The kids were fighting on all sides and Maxie was too intent on trying not to get hurt to see what anyone else was up to. She knocked two fathers down and gave a little scream as she found herself face to face with a hippo, the teeth in its lower jaw as big as any tyrannosaurus’s.

She swore and looked round. Big Mick was backed into a corner with no space to manoeuvre.

‘We have to stick together,’ she shouted. ‘Don’t get split up!’ And she waded in to help Mick, spearing a mother in the back and twisting her weapon to free it. Big Mick swung at the mother’s head as she went down and thanked Maxie.

‘Listen!’ he said and turned towards the door.

Maxie could just make out noise in the corridor. Commotion. Her mood lifted. Maybe help had arrived?

‘Keep going!’ she yelled, kicking another mother in the gut. ‘They haven’t forgotten us.’

Achilleus was going as fast as he could, but still lagging behind the rest of the group. He was right at the back with Paddy, his breath wheezing in his throat.

‘You all right, Akkie?’ Paddy asked and Achilleus slapped him round the back of the head.

‘Course I’m all right,’ he snarled. ‘Keep moving. I just don’t want to get ahead of you.’

‘I can go faster.’

‘Shut up, Paddy.’

But Achilleus couldn’t go on. His vision was blurring, everything going dark around him. His legs felt loose and rubbery. He had to stop. He rested, leaning on a stuffed lion. He was sweating, his head pounding, his throat dry. He closed his eyes for a second, but that just made him more aware of the throbbing in his head. He forced them open again. Glared at Paddy.

‘What you waiting for, caddie? There’s work to do.’