‘Ready?’ Kate says, and we all nod. And then we walk up the steps into the school that kicked us out so painfully, so many years ago.

OH GOD. IT’S not even an hour into the evening and I’m not sure I can do this any more.

I am sitting on the toilet, my head in my hands, trying to get a hold of myself. I have been drinking from nerves, letting my glass get topped up by passing waiters, not counting my units. It feels like a dream, one of those where you’re back at school, but everything is subtly different, more technicolour, everything has shifted up a gear. There was a slightly nightmarish quality to the wall of faces and voices that greeted us as we entered the hall, a mix of total strangers, and of half-remembered faces changed by age, the features sharpened as puppy fat fell away, or alternatively thickened and flattened, the skin loosening imperceptibly like a latex mask that has slightly slipped.

And the worst is, everyone knows us, even the girls who arrived at the school after we left. I hadn’t anticipated that. The way we left, slipping out between one term and the next, our departure unannounced … it felt low-key. It was one of the things the headmistress said to my father at the time, ‘If Isa leaves of her own volition, we can keep this very quiet.’

But I had forgotten the echo chamber we left behind, where the space left by our absence must have been filled over and over again by rumour and speculation until an edifice of lies and half-truths had built up, fuelled by the meagre facts of Ambrose’s disappearance. And now – enough old girls live locally to have seen the Salten Observer. They have read the headlines. And they’re not stupid – they have put two and two together. Sometimes they’ve made five.

The worst of it is their eyes, which are avid. People are pleasant enough to our faces, though their conversation feels a little forced, and I sense, though maybe I’m imagining it, a kind of wariness behind their smiles. But every time we turn away, I can hear the whispers behind our back start up. Is it true? Weren’t they expelled? Did you hear …?

The memories are no longer gentle little ‘do you remember?’ taps on my shoulder, they are slaps, each one an assault. Even away from the crowd they keep coming. I remember sitting crying in this very stall because a girl, a harmless little first year, had seen me and Fatima coming back from Kate’s one night, and I had completely overreacted. I had threatened her, told her that if she told anyone what she’d seen I would ensure she was sent to Coventry for the rest of her days at Salten. I could do that, I told her. I could make her life a misery.

It was a lie of course. Both parts. I couldn’t have isolated her like that even if I’d wanted to. We were too isolated ourselves, by that point. Seats were mysteriously saved in the buttery when we tried to sit in them. If one of us suggested a particular film in the common room of an evening, the vote somehow always went the other way. And besides – I would never really have done it. I only wanted to scare her a little, keep her quiet.

I don’t know what she did or said, but Miss Weatherby called me into her office that evening and gave me a long talk, about community spirit, and my responsibility to the younger girls.

‘I’m beginning to wonder,’ she said, her voice full of disappointment, ‘whether you truly have it in you to be a Salten girl, Isa. I know that things at home are very hard, but that doesn’t excuse your snapping at others, particularly those younger than yourself. Please don’t make me talk to your father, I am sure he has enough on his plate right now.’

My throat had seemed to close up with a combination of shame and fury. Fury at her, at Miss Weatherby, yes. But mostly at myself, for what I’d done, for what I’d allowed myself to become. I thought of Thea, that first night, her account of how the Lying Game had started. I won’t pick on the new girls, the ones who can’t defend themselves, she’d said. I’ll do it to the ones in charge – the teachers, the popular girls. The ones who think they’re above it all.

What had I become, threatening eleven-year-olds?

I thought of what my father would say if Miss Weatherby called him, between trips to the hospital. I thought of how his face, already grey with worry, would tighten more in lines of disappointment.

‘I’m sorry,’ I said, forcing the words out. Not because I didn’t want to say them, but because of the constriction in my throat. ‘I really am. Please – it was a mistake. I’ll apologise. And I’ll try harder, I promise.’

‘Do,’ Miss Weatherby said. There was something worried in her eyes. ‘And, Isa, I know I’ve spoken to you about this before, but please do consider mixing more. Tight-knit friendships are all very well and good, but they can close us off from other chances. They can cost us a great deal, in the end.’

‘Isa?’ The knock on the cubicle door is low but decisive, and my head comes up. ‘Isa, are you there?’

I stand, flush, and leave the safety of the toilet cubicle to wash my hands at the row of sinks. Thea is standing by the dryer, her arms folded.

‘We were worried,’ she says flatly. I grimace. How long had I been in there? Ten minutes? Twenty?

‘I’m sorry, it just … it was all too much, you know?’

The water is cool on my hands and wrists, and I suppress an urge to splash it over my face.

‘Look, I understand,’ Thea says. Her face is gaunt, her thinness making her look almost haggard in the unforgiving lights of the school toilets – the guest facilities have been updated too and now feature soft towels and scented hand cream, but the lighting is just the same as it was, harsh and fluorescent. ‘I want to get out too. But you can’t hide all night, they’re about to sit down for dinner and you’ll be missed. Let’s get through the meal and then we can get out.’

‘OK,’ I say. But I can’t make myself move. I’m holding on to the basin, feeling my nails against the porcelain. Shit. I think about Freya back at Kate’s, wonder if she’s OK. I am almost overcome by the urge to duck out of here and run back to my soft, warm, home-smelling baby. ‘Why the hell did Kate think this was a good idea?’

‘Look.’ Thea glances over her shoulder at the empty cubicles, and lowers her voice. ‘We discussed this. You were the one who voted to come.’

I nod grimly. She’s right. And the thing is, I understand Kate’s panicked reaction, scrabbling around for a reason to explain all her friends coming down here after so many years’ absence, the weekend that a body just happened to turn up in the Reach. The reunion must have seemed like a heaven-sent coincidence. But I wish, I wish she hadn’t done it.

Shit, I think again, and I feel the swear words bubbling up inside me, a poison I can’t contain. I have a sudden vision of myself sitting down at the white-clothed dining table and letting them spew out – Shut your fucking faces, you rumour-mongering bitches. You know nothing. Nothing!

I breathe, slow and quiet, try to steady myself.

‘OK?’ Thea says, more gently. I nod.

‘I’m OK. I can do this.’ Then I correct myself. ‘We can do this, right? I mean, God knows, if Kate can, I can. Is she holding up?’

‘Just,’ Thea says. She holds open the toilet door and I make my way out into the echoing hallway, empty now except for a few teachers milling about, and a large easel at one end, holding the table plans.

‘Ooh, be quick!’ a teacher says, seeing us emerge. She is young, too young to have been there when we were. ‘They’re sitting down for the speeches. What table are you on?’

‘Pankhurst, according to the woman who was here before,’ Thea says, and the teacher looks at the list, runs her finger down the names. ‘Thea West,’ Thea supplements.

‘Oh, that’s right, you’re here. And you are …?’ She looks at me. ‘Sorry, as you can probably tell, I’m a recent arrival so all of you old girls are new faces to me!’

‘Isa Wilde,’ I say quietly, and to my relief her face, as she turns to check the list, registers neither recognition nor shock, just concentration as she scans the tables.

‘Oh yes, Pankhurst too, with a few others from your year by the looks of it. It’s a table of ten on the far side of the hallway, by the buttery hatch. Best way round is to slip in this door and edge round underneath the gallery.’