Ed sighed and rested his head in his hands. All good things came with bad things.

‘Her sister?’ he asked. ‘Dot?’

‘She’s fading fast. We all are.’

Trio put a hand on Ed.

‘We learnt so much before she died. She taught us everything she knew. And Dr Norman as well.’ She smiled at him and he blushed like a teenager. ‘He pretends not to remember. But he’s still got it.’

‘We passed our knowledge on to a new generation,’ said the doctor. ‘We’re the last of the old world. We’ll all be gone soon. This place will be empty, apart from ghosts. All most of us want now is to be able to sit in the sun one more time. It’s a ghastly world out there, beyond these walls. It seems that every generation leaves behind a mess for the next one to clean up.’

‘We’d better go,’ said Ed.

‘Won’t you at least stay for some lunch?’

‘Sorry.’ Ed shook his head. ‘We’ve got to get back to London.’

‘We’ll need some time,’ said Trey. ‘We’ve got to get our stuff together, and there’s some useful equipment that Amelia said we could take. I mean, there’s a few last things I want to … I need to … there’s a spider on the wall …’

‘What?’ Ed looked at Trey. His eyes were twitching, darting about.

‘Blue, Bluetooth, Blu tack … Blu-Tack Bill can count them all … My helicopter … my hovercraft … there are three … bright eyes … they’ve taken bright eyes … I won’t fight …’

‘Are you OK?’ said Brooke, although it was clear that Trey wasn’t. And Trio had closed her eyes now, her head lolling.

Trey’s eyes began to slowly roll back in his head and then he flopped forward. The doctor gently helped him down so that Trinity was lying on the table top.

‘It’s been happening more and more lately,’ he said. ‘Mister Three’s been getting worked up all the time. He’s very agitated. I do wish we could understand more of what he says, though.’

Sure enough Mister Three was uncurling from where he nestled on Trinity’s back. His bulgy eyes opened and he shuddered, shook himself, like a dog having a bad dream.

And then suddenly he was screaming.

‘You’ve got to go! Before it’s too late!’ He was waving his tiny arms frantically, looking around the faces of the kids with a deranged expression. ‘You’ve got to go fast and you’ve got to help the others in London the others they’re in terrible danger you have to help get there as soon as you can they’re being massacred killed … Sam! Sam! They’re after Sam! Help him help the boy they’ve killed the boy you have to help us! They’ve killed the boy …’

His voice got louder and more demented, growing to a shrill, piercing shriek.