I am looking up, looking into space as I think all this out, and then suddenly my eyes focus on something, on a movement outside the door.

And I realise what it is.

The guard is back – the police guard at my door. Only this time I have absolutely zero doubt: they are not there to protect me. They are there to keep me in. I’m not going home when they discharge me, I’m going to a police station. I will be arrested, and questioned, and most likely charged if they think they can make this stick.

Coldly, dispassionately, I try to examine the last person at the hen night: the case against myself.

I was there. I could have sent those texts to James. I could have swapped the live round for the blanks. I had my hand on the gun when Flo fired. What could be more easy than nudging the barrel to ensure it was pointing at James as he came up the stairs?

And, more importantly, I was there at the second half of James’s murder. I was in the car when it drove off the road.

What the hell happened in that car? Why can’t I remember?

I think back to what Dr Miller said: Sometimes the brain suppresses events that we’re not quite ready to deal with. I suppose it’s a … coping mechanism, if you will.

What is it that my brain cannot cope with? Is it the truth?

I realise I’m shivering as if I’m cold, even though the heat of the hospital is as stifling as ever, and I pull Nina’s cardigan from the foot of the bed and huddle it round myself, breathing in her scent of fags and perfume, trying to steady myself.

It’s not the thought of being arrested and charged that has shocked me so much – I still don’t believe that will really happen. Surely, surely if I just explain everything they will believe me?

What has really knocked me off balance is this: someone hates me enough to do this. But who?

I don’t let myself think about the final possibility. It’s one too horrible for me to allow it into my mind, except in tiny niggling whispers when I’m thinking about other things.

But as I huddle down beneath the thin hospital blanket, Nina’s cardigan around my shoulders, one of those whispers comes: What if it’s true?

The rest of the day goes slowly, as if I’m moving through air made of treacle. It feels like the nightmares I sometimes have where my limbs are too heavy to move. Something is pursuing me, and I have to get away, but I’m stuck in mud, my legs are numb and slow, and all I can do is wade painfully through the dream, with the unspecified horror behind me getting closer and closer.

My little room feels more and more like a prison cell, with the narrow hatch of reinforced glass, and the guard outside the door.

If they release me, I know now what will happen. I will not be going home. I will be arrested, and taken to a police station, and then probably charged. The texts are enough evidence to hold me, along with the fact that I denied having sent them.

I remember, a long time ago, when I wrote my first book, speaking to a policeman about interviewing techniques. You listen, he said. You listen for the lie.

Lamarr and Roberts have found their lie: I told them I did not send those texts. And yet, there they are.

I try to eat, but the food is tasteless and I leave most of it on the tray. I try to do a crossword, but the words fall away from me, they are just typing on a page and my mind’s eye is being invaded by other pictures.

Me, in the dock at court, in a prison cell.

Flo, on life-support, somewhere in this very hospital.

Clare, flat on a bed, her eyes moving slowly beneath her closed lids.

James, in a pool of spreading blood.

Suddenly my nostrils are filled with the smell of it – the butcher’s shop smell of his blood on my hands and my pyjamas and leaching into the floor …

I throw off the covers and stand up. I walk to the bathroom to splash my face with water, trying to wash away the stench of blood and the invading memories. But the memories I want don’t come. Is it possible … is it possible I did send those texts, and I have just buried it along with whatever happened in the car?

Who can I trust, if I can’t even trust myself?

I put my face in my hands, and when I stand, I look at myself in the mirror, beneath the unforgiving fluorescent light. The bruises around my eyes are still there, but fading. I look jaundiced, hollow-eyed. There are dark patches in the hollows at the bridge of my nose, and beneath my lower lids, but I no longer look like a freak. If I had concealer I could cover the shadows up. But I don’t. I never thought to ask Nina for that.

I look thin, and old. My face is crumpled where I have been lying on the hard hospital sheets.

I think of the me I am inside. In my head I have been sixteen for nearly ten years. My hair is still long. I find myself going to sweep it back in moments of stress, and it’s not there.

In my head James is still alive. I cannot believe that he isn’t.

Would they let me see his body?

I shiver, rake my wet hand through my crumpled hair, and rub my palms on the grey jogging bottoms.

Then I turn and leave the bathroom.

As I come out of the ensuite it strikes me that something is different. For a moment I can’t work out what it is: my book is still there on the bed. My flip-flops are beneath. My water jug is half full on the locker and the file of notes is still stuck crookedly into the holder at the foot of the bed.

Then I see.

The guard is not there.

I walk to the door, peering out through the wire-hatched pane. The chair is there. A cup of tea is there, steaming gently. But no guard.

A little prickle of adrenaline runs through me, making the hairs on my neck shiver. My body knows what I am about to do, even before my mind has processed it. My fingers are reaching for the flip-flops, easing them on. My hands are buttoning Nina’s cardigan. Lastly I reach for the two ten-pound notes, still lying, folded, on the corner of the locker.

My heart is thumping as I press gently on the panel of the door, expecting at any moment to hear a shout of Stop! or just a nurse saying ‘Are you all right, dear?’

But no one says anything.

No one does anything.

I walk out of the room and down the corridor, past the other bays, with my feet in my flip-flops going plip, plip, plip against the linoleum floor.

Past the nursing station – there is no one there. A nurse is inside the little office but her back is to the glass, doing paperwork.

Plip, plip, plip. Through the double doors and out into the main corridor, where the air smells less of Lysol and more of industrial cooking from the kitchens down the corridor. I walk a little faster. There is a sign saying ‘Way Out’, pointing round a corner.

As I turn it, my heart almost stops. There is the police officer, standing just outside the men’s toilets, muttering into his radio. For a moment I falter. I nearly turn tail and run back to my room before he can discover I’m gone.

But I don’t. I recover myself and I walk on past, plip, plip, plip, with my heart going bang, bang, bang in time with my steps, and he doesn’t give me a second glance.

‘Roger,’ he says as I pass him. ‘Copy that.’

And then I round the corner and he’s gone.

I keep walking, not too fast, not too slow. Surely someone will stop me? Surely you can’t just walk out of a hospital like this?

There’s a sign saying ‘Exit’, pointing along the corridor between cubicles of beds. I’m almost there.

And then, as I’m almost at the last door before the lift lobby, I see something, someone, through the narrow pane of glass.

It’s Lamarr.

My breath catches in my throat and, almost without thinking, I duck backwards into a curtained cubicle, praying that the occupant is asleep.

I edge the curtains stealthily around myself, my heart banging in my throat, and stand, waiting, listening. There’s the noise of the main ward doors opening and closing, and then I hear her heels going click, clack, click, clack down the linoleum floor. At the nurses’ station, almost opposite the cubicle where I’m hiding, the steps pause, and I stand, hands trembling, waiting for the curtain to be ripped back, waiting for the discovery.

But then she says something polite to the matron on duty, and I hear the heels go click, clack, click, clack, down the corridor towards the toilets and my room.

Oh thank God, thank God, thank God.

My legs are weak and shaking with relief, and for a minute I don’t think I can stand. But I have to. I have to get out of here before she gets to my room and realises I’m gone. I suddenly wish I’d thought to put pillows in the bed or draw the little curtain across the window.