I swallow, hard. I look deliberately away from where the mask is hanging, in case he realises that I really do recognise his mask and could expose him and then decides to kill us both and feed us into a wood-chipper. I don’t know. Anything could happen.

‘She can sense it,’ Shandy says. ‘We know it’s you. Don’t mess about.’

I’m beginning to feel some small measure of respect for Roman and Donato. The two of them are elegant professionals compared to Shand and me.

‘OK, never mind that,’ I say. ‘It’s not why we came.’

‘That’s . . . good . . .’ he says carefully. ‘I’m sure you know that if you’re dreaming about me, that’s something between you and your therapist. And it’s definitely not an appropriate topic of conversation between us. You may blame me for your situation, but it’s not my responsibility.’

‘Maybe you can’t be held accountable, legally,’ Shandy says, leaning forward and fixing her glittering black eyes on his face. ‘But morally you must feel something. You trialled this therapy on my friend and she’s got long-term issues now and you feel nothing?’

‘I didn’t say I feel nothing. If I felt nothing I would have called the police and reported you for harassment – which, by the way, is well within my rights. You’ve stalked me at my home. I’m sorry that you had a bad experience, Charlotte, but please don’t demonise me. I’m not even at BigSky any more. I’m not in a position to help you.’

I say, ‘What do you know about a neural repair treatment given for dementia?’

‘This feels like an interrogation. BigSky has worked on several dementia treatments, but I’m not involved with any of them.’

‘And did any of them induce sleepwalking?’ I press.

‘Can’t say. Legally, I’m not permitted to discuss it with you.’

‘I want to know why you left BigSky and moved to a start-up,’ Shady says.

‘I was recruited.’

‘But you can’t possibly be making the same sort of money at a start-up as at BigSky,’ she challenges.

‘Money isn’t the biggest motivator. It’s the work that interests me.’

‘Or was it that BigSky sacked you when they found out about the cock-up?’

I step on her foot and interject in a rush, ‘I want you to introduce me to Meera Bhango.’ It’s the only thing I can think to say – anything to deflect from the accusations Shandy has made, accusations that are going to make him want to kill us if he is the Creeper.

His reaction surprises me. He’s taken Shandy’s allegations in stride – looked almost amused – but suddenly he won’t meet my eye and he fidgets in his ergonomic desk chair.