Guilt: The Sunday Times best selling psychological thriller that you need to read in 2018

‘Please think,’ the DI insists.

‘My sister never got angry. Not like that. I had never seen her like that.’

His words rotate in her head.

‘Detective Inspector, my client is extremely distressed. Mentally incapable of continuing this interview. I request she is allowed some sleep and that we continue this tomorrow, when everyone is a bit fresher,’ Richard Mimms demands.

DI Irvine presses the tape recorder button again.

‘Request allowed,’ he says. Richard Mimms collects his papers, crinkling his eyes at her as he leaves.

Back in her cell, all she can think about is her sister’s cold, dead, fish-like eyes. She lies awake all night on the hard trundle bed, shivering and trembling.

In the morning, breakfast is a piece of dry toast, and lukewarm coffee in a disposable cup. She feels as if someone has punched her in the stomach, so she cannot touch the toast. One sip of the metallic-tasting coffee and she pours it down the sink. Then Sergeant Hawkins appears, to take her back to the interview room.

Once there, she begins to hear her sister’s voice screaming in her head. A hysterical scream becoming louder and louder. Trying to push her sister’s scream away she sits down next to Richard Mimms. She can smell his aftershave. Herbal. Overpowering. DI Irvine and Sergeant Hawkins are opposite, their accusing eyes pushing towards her. She watches a finger pressing the button of the recording machine. The date is announced. The names of all present. And the interview begins again.

‘Tell me, when did you first see your sister yesterday evening?’ DI Irvine asks.

Her words stagnate in her mouth. The screaming is overpowering her. And somewhere through the tears and the darkness and the scream, she answers DI Irvine’s questions. And somewhere through the tears and the darkness and the scream, she hears the words.

‘You are charged with the murder of your sister.’

Charged. Murder. Sister. Sister. Murder. Charged.

Words slipping through her brain as she is escorted back to her cell.

THE PAST (#u7eb7f9cb-c54d-500b-bb37-1f24a57f8ffd)

2 (#u7eb7f9cb-c54d-500b-bb37-1f24a57f8ffd)

Miranda (#u7eb7f9cb-c54d-500b-bb37-1f24a57f8ffd)

‘Zara, you need to go to Tesco to buy something for supper,’ I say as I sink exhausted into my brown leather sofa after yet another day selling my soul as an accountant with Harrison Goddard.

You sigh impatiently and raise your eyes to the ceiling. You’ve been living with me for two weeks and it is only the second time I’ve asked you to do anything.

‘Isn’t there something in the fridge?’ You pout.

‘Why don’t you take a look? It’s your turn to cook.’

You open the fridge door to inspect the contents. I know only too well what you will see. Cans of lager and the garlic dips from our takeaway pizza last time it was your responsibility.

‘Mmm delicious, lager and garlic – what’s wrong with that?’ you announce.

So hopelessly undomesticated, and yet I can’t berate you. Sometimes your incompetency, your vulnerability, make me love you more than ever – my unidentical twin sister, who I feel so responsible for. Your eyes smile into mine and we both start to laugh. You lift your arms in the air in surrender.

‘All right. All right. See what you mean. I’ll go.’

You are gone a long time. So long I begin to worry. Mother and I, we always worry when you move off radar. You’ve been living with Mother for years, doing a filing job in our hometown. It has taken over ten years since leaving school for you to find the confidence to apply for a degree course. Now you’ve moved to Bristol, a mature photography student at UWE, it’s my turn to look out for you. And I need to look out for you. Because you’re a cutter.

And twice you have cut too deep.

Once, a very long time ago when we were at school. I still remember that winter afternoon so clearly. Walking to meet you from your netball session, after my hockey had finished. A perfect winter afternoon. Sunny, with a nip in the air. The sort of afternoon that fooled for a second, making me believe I was walking through a ski resort. But something was wrong. People were staring at me. Whispers on the wind.

‘Zara. Zara Cunningham.’

‘They called the ambulance and the police.’

The PE teacher told me what had happened.

‘Your sister slit her wrists.’

A slow creeping numbness seeped through me.

‘The PE assistant found her unconscious covered in blood. This afternoon, just before netball.’

‘Is she all right?’ I asked with a tremor in my voice.

The PE teacher put her hand on my shoulder. ‘We found her in time. I am sure she’ll have regained consciousness by now.’

In time. Regained consciousness. The PE teacher’s words jumped in my mind. Zara, I wanted to know how you could do this to yourself. How could you try to take your own life? You whose life always seemed so much more interesting, so much more carefree than mine.

But it wasn’t like that, was it? You hadn’t tried to kill yourself. Cutting seems to give you some sort of euphoria.

‘I cut to take the pain away,’ you told me later. ‘And to stop the panic attacks.’

‘What pain?’ I asked. ‘How can more pain take pain away?’ I paused. ‘And what panic attacks?’

The second time you cut too deep by mistake was only six months ago. Just when Mother and I thought that maybe at thirty years old, after so many years of antidepressants and CBT, maybe you had stopped doing it. A phone call to Harrison Goddard to inform me. Just as I was tidying my desk, about to go for lunch. Mother’s voice on the line, riddled with panic, only just recognisable.

‘Come quickly Miranda. She’s slit her wrists again. Deeper this time. The paramedic said it’s touch and go whether she’ll survive.’

I left work immediately. I drove up the motorway to our hometown, the world passing me in a blur. When I arrived at the hospital I scrambled out of the car and allowed the place’s sprawling bowels to swallow me up. I felt as if I was floating. The hospital seemed to move around me. People being triaged. The reception desk protected by an armoury of glass, with only a thin slit for conversation. The receptionist was busy. Tapping a computer keyboard with her long blue tapered fingernails. No time to look up. The phone on her desk rang. She picked up, frowning as she listened.

‘OK, OK. Will do.’

She put the phone down. At last she looked up and noticed me. ‘Can I help?’ she asked.

‘I’m looking for my sister, Zara Cunningham. She was admitted earlier. My mother is with her.’

Blue fingernails stabbed at the computer keyboard again. ‘She’s in Critical Care. I’ll get a nurse to take you to her. Wait by the door to A&E.’

‘Thanks.’

I stood by the door, as requested. Bracing myself to wait for a long time. But no sooner had I arrived than a plump, blonde nurse wearing a pink uniform was putting her head around the door asking me whether I was Ms Cunningham. No sooner had I said yes than I was escorted into the unknown depths of A&E.

‘I’ll take you to find your mother,’ the nurse said.