Kenny speaks again. His voice is deep and slow, so clear that it cuts over everything else. As always, there’s a delay between each word while I digest the last.

‘You have to run right now.’

The adrenaline erupts. My heart pounds. Sweat fizzes all over me.

‘Run now, Ollie. Or die.’

And so I run.

2.59 p.m.

The ground races under my feet. Only when running is my brain silenced – all I hear are my own desperate gasps for breath and the slap of my shoes against concrete.

I stumble to a halt. I’m twenty metres outside the school gates. The semis lining the road seem to be dozing in the sun, only a distant lawnmower thrumming through the still air.

I know it’s five minutes forty seconds to the train station from here, give or take twelve seconds. I know it’s less if I run. I know that any minute now there will be an explosion. But I know nothing else.

I face the school. The grounds are deserted, the building silent. I turn away, looking along the road that will lead me away from here. It doesn’t feel exciting. It doesn’t look like freedom. And I don’t know why.

Sophia was not outside the door. And she’s not here. This is where we planned to meet – it’s been discussed a thousand times. We meet here; we walk together to the station. On the way, she phones the school reception, demanding to urgently speak to Mr Clark, getting him called away from the classroom – I hate the bloke, but I’ve never wished him dead.

That’s always been the Plan. But she’s not here.

Is she at the station already, waiting for me?

It’s possible she is.

It’s possible she isn’t.

If she’s not there, this is all for nothing.

This is not how I’ve imagined it. It’s all wrong. This is a plan built on certainty, minute-by-minute accuracy. But the foundations are gone; the structure is tumbling around me. I know nothing now – nothing for certain.

For a second, I can picture being at the station without her. Hearing the blast. Boarding the train. Alone. The vision is inhuman. It’s barbaric.

I can run now, into the vast and silent world ahead of me, praying that she’ll be there. Or I can run back through those gates, undo what I’ve done. Either way, right now I need to be running. Doing nothing is not an option.

The decision comes in the minuscule space between my hammering heartbeats. Like snatching a hand from a boiling saucepan, the command to move bypasses my brain. With my first step, the direction is set.

The ground reels beneath me once more. And again the racket in my mind is gone.

3.04 p.m.