I flip the catch on the hatch on the first door. It slides down smoothly to reveal an opening into the room, striped with steel bars, like a prison cell. I have to stand on my toes to be able to see inside the room, and what I see makes me shudder. It’s all white on the inside, and the walls and ceiling are covered with a strange textured material, forming rows and rows of identical bumps like rounded-off plastic pyramids.

‘It’s sound-proofed,’ I say.

‘Another good sign,’ Karim says.

There’s a bench with a mattress laid on it across the far wall, but other than that the room is clear. ‘It’s set up for someone to be kept here, but it’s empty.’ I don’t know if I’m disappointed or relieved.

‘I’ll do the next one,’ Karim says, opening the hatch and clinging to the rim of it with his fingers so he can pull himself up a bit. And then he calls out, ‘Mum!’ And it’s not his fault, but it’s way too loud – the sound bouncing off the walls and echoing around us. I instinctively pull him back 92 and clasp my hand over his mouth, holding it for one, two, three beats before I let go.

He takes a breath. ‘Sorry. Can we get her out?’

Kat and I tiptoe to look in the hatch. The room is the same as the last one I checked, but this one has Karim’s mum lying on the mattress. My heart sinks when I see her. She has a small cut on her forehead but looks unhurt other than that. The problem is…

‘She’s asleep,’ Kat whispers.

‘She doesn’t look too bad.’ Karim bites on a nail. ‘I’m sure she’ll be able to walk out of here, if we can just get the door open.’

‘Karim,’ I say, holding his shoulders and looking him in the eye. ‘She’s asleep.’

He looks from me to Kat, then back again.

‘She might just be resting.’

‘I’m sorry, Karim,’ Kat says, ‘but we’re too late. If we wake her up now, things will get a lot worse.’

I see his eyes gloss over. I see him swallow as he tries to compute what’s happening and stop himself from crying.

‘We can get her back,’ I say. ‘Like we’re going to get my mum back, and everyone else who’s been turned. Like we did with Chets.’

93 ‘Can’t we just try to wake her? She might be OK; we don’t know for sure that everyone in Straybridge is being body-snatched by alien spores.’