‘What we gonna write?’ she asked, making no effort to keep her voice down.

‘You’re nuts. You know that?’

‘You never done something like this before?’

‘Not exactly.’

‘Sometimes it’s good to be bad, Ollie. And this place deserves it.’ She strolled out from under the tree and stood on the open grass halfway to the classroom. Facing the main school building, she stood on tiptoes and thrust her arms out behind her. ‘Come and get us, Five Oaks fuckers!’ she yelled into the night.

I eased myself backwards so I was standing with the massive tree trunk between me and the school. The bark of a distant dog was just audible over the squelching of my own heartbeat in my ears.

‘See. No one here,’ she said, laughing. ‘Five Oaks fuckers!’ she shouted again, leaping in the air as she delivered the last word, like she was punching a volleyball.

I took a deep breath, hoisted my schoolbag on to my shoulder and jogged across the slippery grass towards her. ‘You’re crazy,’ I said as I approached. ‘The caretaker’s probably still on duty. I think he actually lives here.’

‘Can you run faster than him?’

‘No idea. Don’t recall him taking part in sports day.’

‘I’ll keep watch; we’ll have a head start.’

I dropped my bag to the ground behind the Portakabin. This was without doubt the worst behaviour I’d ever indulged in, but there was no question of ducking out now. The aerosol cans rattled as I tipped them out on to the grass.

Sophia knelt beside me and weighed each one in her hand. ‘This one’s the fullest – start with this.’

Most of the cans strewn about the works had been empty, but we’d gathered seven that still had some paint left in them.

‘What colour is it?’ I asked as if it mattered.

She rattled the thing as hard as she could, surely revealing what we were doing to anyone within a quarter of a mile. ‘Nice bright red,’ she said, puffing a splodge on to the timber panelling. She smiled at me and sprayed a little red heart in the corner of the building. ‘Shall I put our initials in it?’ she asked.

I grinned back at her. My mouth was dry, my breathing short. ‘Maybe not the best idea.’

She made an exaggerated sad face. ‘Spoilsport.’

There was only one thing to do. Like getting into a freezing sea, a slow entry was going to hurt with every step, and make me look like a wimp into the bargain. Diving straight in was the only option. ‘Give me the can,’ I said, hoisting my foot on to the narrow window ledge and gaining a handhold on the guttering.