The next big thing happened in the main hall, which was now in meltdown. As soon as Sam and I opened the door, we felt a wave of hot outrage escaping, and the noise was unbelievable. Almost every single person in that room seemed to be arguing.

My sister was standing with her back against the wall, pretending to be cool, while parents tried to sort kids out, standing between fighting ones, holding back shoving ones, and it was impossible to work out what had started it. Sam and Roan’s mum is called Cindy. She stood red-faced in the middle with my mum, and warring kids swirled around them. Mum looks so funny when she’s helpless; it was murder trying to keep my face straight.

‘Sick!’ Sam said. ‘That thing you let loose must be strapping!’

The air was getting even heavier.

‘Feels exactly like a thunderstorm,’ Sam said, wiping the sweat off his face.

I nodded. ‘The weather weirdness has definitely got more intense since I let that thing out of its box. We need to think happy thoughts to calm it down.’

‘What? Why?’

‘When Mr Lombard said all that stuff, the weather got worse, just like it was matching my feelings. So if both of us concentrate on generating good feelings …?’

He shrugged. ‘OK then.’

‘Happy thoughts,’ I said, humming. ‘I’m thinking of going trampolining with Lily. We used to do that loads. What are you thinking about?’

He shook his head at me. ‘You’re making too much noise for anyone else to think at all!’

I pulled my best monster face and dug my elbows in his ribs till he laughed. I think it started working, because Sam’s little brother Roan had been in the middle of the row, but now he left the person he’d been arguing with and weaved between the bodies instead, moving his neck like a chicken and laughing his head off. The heat in the room lifted slightly. Someone opened a window. Sam laughed in amazement and gave me a thumbs-up.

In less than a minute a youth club leader came in and started sending everyone home. We went to get our coats while our mums collected their baskets of supplies – but then something rumbled behind the cloakroom wall. There was a tearing sound. The floor vibrated, and so did my legs.

We spoke together. ‘It’s in the walls!’

13

Cosmic Background Radiators

Sam and I stepped backwards, feeling our way to the cloakroom entrance without taking our eyes off the wall. We hardly breathed. Out in the main corridor, kids still clattered around.

Something scraped along inside the wall. My hair roots tingled, and Sam’s hair lifted by itself – way up in the air.

‘It’s following you, Alfie!’ Sam said.

I pulled a puzzled face.

‘It’s going wherever you are!’

The noise stopped, as if it was listening to us.

‘Alfie, let’s go.’

‘Wait!’