The building is mostly dark, though individual 277 windows light up in sequence, one after the other, as though someone is moving methodically from room to room. There are a couple of bug security guards patrolling the outside. They walk the perimeter of the building, stopping every ten metres or so to look out across the campus, the yellow rings in their eyes standing out in the darkness. Other than that, it’s suspiciously quiet and calm. Ade was planning to set off the fire alarm to lure the bugs back to base. She obviously managed it, as it did the job, but they’ve got it switched off and things back to normal super-fast. I hope she’s OK.

‘See you on the other side,’ Mak whispers, and then he disappears into the darkness like a pro. Our group feels small without him and Ade, but Kat, Karim and I got in yesterday, so we can do it again today.

We time it so that the guards have moved out of sight, then Kat scales the wall to the broken window in just a few seconds. I don’t know how someone can be so strong and light as air at the same time, but she’s got it down without even looking like she’s trying. If we get through this, I might see if she’ll come to the climbing centre  278 with me and try to teach me some skills. I’ll probably be rubbish, but it’ll be fun anyway. A minute later, she opens the door for us and we sneak inside.

‘Good luck,’ she whispers, hugging us both, and then she’s out the door, closing it gently behind her. She’ll be on the roof before we’re halfway up the corridor. The lights flick on as we walk, and I realise how hard it’s gonna be for Karim to get up to his mum’s office without being stopped. The lights give away our location at every step, and we’re so exposed.

‘Karim,’ I say. ‘I’m going to get into the central hub and create the diversion. Whatever happens, you have to get to that office.’

‘I know,’ he says. ‘But don’t do anything dangerous.’

I stop walking and turn to him. ‘Seriously, man, whatever you hear, it’s all part of the plan. Promise me you’ll keep going and get into your mum’s computer. We have to get the XGen back on. No pressure.’

‘I promise,’ he says. ‘I can get into her computer easy, and I’m sure I can find my way around the XGen software. You can trust me.’ 279

‘I have no doubt,’ I smile. And I don’t. My part is simple compared to his, or Kat’s or Mak’s. Simple, but not easy.

‘Wait for one minute after I go through the door,’ I say. ‘Then get up there as fast as you can without getting caught.’