‘Well, kind of. I think it would help people learn quicker and be smarter, but it could also influence people without them even knowing they were being influenced.’

‘Or it could programme people to say, or believe, or do anything?’

Thea looked at the image paused on the screen: Delores was caught mid-gesture in a blur, which made it look as if Moses was reaching out to a ghost.

‘Yeah, I guess so.’

Ethan pushed the laptop away from him a little and rubbed at the cloth taped around his head.

‘Well, this just gets better and better,’ he said sarcastically. ‘Not only am I acting out my hallucinations, but if I’m lucky and the tech works properly, I get my mind reprogrammed to eat a certain brand of crisps, and – gee – I don’t know … maybe go kill the prime minister.’

‘Keep watching.’

He did. Thea didn’t want to see it again, Ted’s face, so she watched the snow come down. At first, she’d thought it wouldn’t settle. The ground had been so wet from the sleet, but it had and now big, fat, feathery flakes floated lazily in the dark, giving the fields a duvet day that Thea would see the next morning. She was beginning to lose track of time. They’d been at the lighthouse for only one day and the trial itself was in its fourth week. The snow fell and the window was a square of static interference on a television screen. They couldn’t have got back to the Sleep Centre even if they’d wanted to; they were wearing warm layers, a fleecy top and thermal jacket, but only trainers on their feet, the monastery search party intending to be back well before the snow.

No, that was wrong, Thea thought; they could still get back to the Centre. It would be cold and miserable and they’d probably twist an ankle because they couldn’t see the path anymore, but they could do it. They just didn’t know whether that was the best idea yet. And the snow was a good excuse.

One day gone already. Why hadn’t anyone come to get them? The Centre knew where they were and, yes, there was snow, but that wouldn’t stop them. Ethan had heard of a fire at the Centre from the radio of one of the search party guards. Was that keeping them busy? How much longer would that last?

Ethan was silent when the video diary ended.

‘I think it’s when you go into Phase Three, remember – the bit where we get to improve ourselves?’ Thea spoke quickly. ‘I think that’s where it all starts to go wrong. Ted was learning all those languages—’

‘Jesus! Did you see him?’