I enter the second tunnel, leaving the sunshine behind me again. When I come out the other end, I think of a baby’s first breaths, gasped in the midst of all that new brightness and noise. I try to envisage a baby’s birth as it should be, because the bad outcomes are the exceptions and it is important to keep that in mind.

‘Helen.’

I halt as if somebody has jerked me backwards. I know that voice, but I blink several times, as if to be sure of what I am seeing.

There is no doubt. The woman standing before me has stepped straight out of my nightmares.

It’s not the right time yet. Getting you out the right way will take time. We need to set things up properly.

It has been almost two years since I’ve seen her, and Zac is a better candidate for the starring role in my bad dreams. But Maxine is the one who comes to me in the night, just as she did on my last night in hospital, the sheets clinging, cold and damp from my sweat.

Maxine has this way of never seeming to look at anyone or anything, her eyes downcast, her shoulders rounded. She is droopy. That is the word I often think of when I observe her. Your eyes would slide over her as if she were the most uninteresting piece of grey furniture ever made. And that is exactly what she wants your eyes to do.

‘It’s good,’ she says, ‘how readily you respond to Helen. Presumably Graham is natural to you too, now?’

‘Yes.’ I hadn’t been out of breath, but now I am.

Maxine’s blouse is elegant in midnight-blue silk, but untucked and sloppy. Her loose black trousers disguise how slim and dangerously fit she is. She is slouchy, as ever. Only the unfortunate know what it means when she straightens her back, something she does rarely. I am one of that select group.

‘You look different.’ That flat flat flatness of her voice. The pretence of indifference, as if I am a neighbour she sees every day, walking up and down the path to the next-door house.

‘That’s hardly surprising.’

Time seems to spool backwards, speeding past her twilight swoop on me in the hospital almost two years ago – it too painful to freeze time there. It rushes further back, past her ambush on the cliffs two and a half years ago. Time stops six years ago, on the day I flunked out, sitting in that white-light room with the exposing glass table between us.

You’re like that puppy who was too friendly to be a police dog, she’d said. We don’t recruit good-looking people. You need to look like Jane Average, but you’re too vain to let yourself look that way.