It wasn’t pretty but it got the job done, ripping out a section of the barbed-wire fence and shoving it to the side so that me, Beverley and Dominic could run through the gap.

‘The farmer’s not going to like this,’ yelled Dominic as we ran past the twisted remains of the fence.

‘He can bill me,’ I said.

Even in my PSU boots, running at night over uneven ground was difficult and Beverley soon pulled ahead of me and Dominic. Out in the open pasture I was suddenly aware of the blue-black vastness of the sky and the river of stars arching over my head. At the far side of the field I could see a smudged line of shadow against the midnight blue of the sky – I hoped it was another fence line because if it was a cliff or something we were in deep shit.

I heard the bellow of a unicorn behind me and, without looking back, I put on a spurt of speed, the long grass whipping around my ankles.

‘There’s a fence,’ yelled Beverley from in front of me.

Doing magic on the fly, even something as basic as an impello variant, is incredibly difficult. Nightingale said that when he was training only half his peers could perform while under physical stress. Which is why, in the Folly, boxing practice goes, jab, jab, right, duck, roundhouse, uppercut, lux, jab, jab, impello.

I stripped away the sound of my own breathing and the impact of my feet on the grass so that in my head there was only the pounding of my heart and the right formae – and then I twisted that shape in the Yale lock of the universe.

Ahead of me I saw bits of shadow splinter and fly away to either side. It wasn’t perfect, but I reckoned that even the Russian Olympic judge was going to give me at least eight points for interpretation.

Then I realised that beyond the fence the land fell away in a sixty degree slope, fortunately a wooded one, and I saved myself by deliberately running into a tree and throwing my arms around it.

Beverley screamed my name suddenly and I heard an angry snort from right behind my head and threw myself to the side. There was a horrible crunching sound and a hole the size of a fifty pence bit appeared in the trunk of the tree I’d been holding. Another snort, frantic this time. Bark spooled off from around the hole in the tree and, with a splintering sound, a crack a metre long appeared above.