He nods. ‘If you see my mum, shove some brownies in her mouth, will you?’

I give him one last smile, pull open the door to the stairwell, and run. This is it now, the only way to get all the sporelings together and away from Karim is by giving them an opportunity that they won’t be able to pass up. I’m down the stairs in twenty seconds, and as I open the door, that god-awful stink whams me in the face. It’s so hot in the building after days of them blasting the heating as high as it will go. The air is beyond ripe, and there’s no moisture anywhere, except for the sweat that’s pouring down my back and soaking through my hoody. As I turn towards the spoke that leads to the hub, I see that the lights are on in the centre of the building. They must be there, protecting the queen.

I’ve thought through a bunch of different ways of sneaking around and distracting the sporelings, 280 but every one of them seemed likely to fail. I need to give my friends the time and space to do what they need to do, or all of us are doomed. So instead of hiding, or creeping, or running, I walk slowly into the hub. I walk like I’m supposed to be there. I walk with swag. And I make it almost all the way to the centre before everything goes crazy.

The hundred-metre Christmas tree is still standing. The smashed ornaments have been cleared away, and at its base, between piles of perfectly wrapped fake presents, is a desk and chair. The ring of bugs around it blocks my view, but I can see that someone is sitting there, surrounded by specimen jars, and a microscope. There must be twenty sporelings forming a protective circle around the desk, plus I see more climbing the walls and patrolling the circular balconies. They’re all guarding whoever is sitting there. The queen.

As I move towards the desk, a sporeling drops to the ground in front of me from somewhere on the ceiling. He’s joined almost instantly by four more – one either side and two behind me. And every bug in the room turns towards me, making 281 the hoching sound that means I’m about ten seconds away from being bombarded with sedative spit missiles.

‘Hold,’ comes a voice from the desk. I hear the chair scrape, and the circle of guards parts to let the queen through. And it isn’t Hoche, but it is someone I’ve met before – six months ago when our coach was stopped on its way into the crater. It’s the person whose notes helped us to defeat the sporelings the first time around.