As well as the debauchery, Barry Grant said, they all neglected to go to the dentist. (Apart from the inmates on the other end of the scale, who went to the doctor, dentist and hospitals far too much, on all manner of trumped-up charges.)

There were lots of reasons why addicts didn’t attend the dentist, Barry Grant went on to explain.

Lack of self-respect was one; they didn’t think they were worth looking after.

Fear of spending money was another. Addicts prioritized their spending so that most of it went on drugs or food or whatever it was they were keen on.

Fear itself was the biggest reason, she said. Everyone was afraid of going to the dentist but addicts never faced up to it. The way they never faced up to anything frightening, she said. Whenever they felt afraid they drank a bottle of whiskey or ate a lorry-load of cheesecake or put their month’s wages on a dead cert.

All fascinating stuff that had me nodding and ‘hmmm’ing. If I wore glasses I would have taken them off and swung them knowledgeably by the arm. Until out of the blue it occurred to me that I hadn’t been to the dentist for about fifteen years.

More, probably.

About nine seconds after that I got a twinge in one of my back teeth.

By bedtime I was demented with pain.

‘Ache’ came nowhere near describing the metallic, hot, electric sparks of screaming torment that shot up into my skull and down into my jaw. It was horrible.

I kept leaping up to grab my jar of dihydracodeine and cram my head full of precious, soothing painkillers. Then stumbling back in confusion as I realized there weren’t any to take. That all those gorgeous little removers of pain were sitting in the top drawer of my dressing-table in New York. Always assuming that it was still my dressing-table, that Brigit hadn’t brought in a new flatmate and thrown my stuff out on the street.

That was far too unpleasant to contemplate. Luckily my toothache was so phenomenally awful that I couldn’t think about anything else for long, anyway.

I tried to bear the pain. I managed a good five minutes before I shouted ‘Has anyone got any painkillers?’ to the dining-room at large.

It took me a moment to figure out why everyone guffawed with laughter.

I went, almost on my knees, to Celine, who was the nurse on duty that night.

‘I’ve got a terrible pain in my tooth,’ I whimpered, my hand cradling my jaw. ‘Can I have something for the pain?

‘Some heroin would do nicely,’ I added.

‘No.’

I was stunned.

‘I didn’t mean it about the heroin.’

‘I know. But you still can’t have any drugs.’

‘They’re not drugs, they’re just things to kill pain, you know that!’

‘Listen to yourself.’

I was bewildered. ‘But it hurts.’

‘Learn to live with it.’

‘But… but this is barbaric.’

‘You could say that life is barbaric, Rachel. Regard this as an opportunity to coexist with pain.’

‘Oh God…’ I spluttered, ‘I’m not in group now.’

‘It doesn’t matter. When you leave here you won’t be in group anymore and you’ll still have pain in your life. And you’ll find out that it won’t kill you.’

‘Of course it won’t kill me, but it hurts.’

She shrugged. ‘Being alive hurts, but you don’t use painkillers for that.

‘Oh no, I forgot,’ she added. ‘You always have, haven’t you?’

The pain was so bad that I thought I was going mad. I couldn’t sleep with it and for the first time in my life, I cried with pain. Physical pain, that is.

In the middle of the night, Chaquie could take no more of me tossing around and scratching my pillow in frantic torment and she marched me downstairs to the nurses’ station.

‘Do something with her,’ she said, loudly. ‘She’s in agony and she’s keeping me awake. And I’ve Dermot coming tomorrow to be my Involved Significant Other. I’m finding it hard enough to sleep.’

Celine reluctantly gave me two paracetamol, which didn’t even make a dent in the pain and said ‘You’d better go to the dentist in the morning.’

The fear was nearly as great as the pain.

‘I don’t want to go to the dentist,’ I stammered.

‘I bet you don’t.’ She smirked. ‘Were you at the lecture earlier this evening?’

‘No,’ I said, sourly. ‘I decided to skip it and went for a few pints down in the village instead.’

She widened her eyes. She wasn’t pleased.

‘Of course I was at it! Where else would I be?’

‘Why don’t you regard going to the dentist as the first grown-up thing you’ve ever done,’ she suggested. ‘The first frightening thing you’ve ever managed to do without drugs.’

‘Oh, for God’s sake,’ I muttered under my breath.

Even though one of the nurses, Margot, went with me, I was the envy of the inmates.

‘Will you try to ESCAPE?’ Don wanted to know.

‘Of course,’ I mumbled, my hand to my swollen cheek.

‘They’ll set the leopards looking for you,’ Mike reminded me.

‘Yes, but if she hides in the river they’ll lose the scent,’ Barry pointed out.

Davy sidled up to me and discreetly asked me to put a both-ways on the two-thirty at Sandown Park.

And on the three o’clock.

And on the three-thirty.

And on the four o’clock.

‘I don’t know if I’ll be near a bookie’s,’ I explained, feeling guilty. Anyway, I wouldn’t have known what to do, I’d never been in a bookie’s in my life.

‘Will you be handcuffing me?’ I asked Margot, as we got into the car.

She just threw me a disdainful look and I cringed. Humourless hoor.

To my alarm, as soon as the car left the grounds, I started to shake. The real world was strange and scary and I felt I’d been away for a very long time. That annoyed me. I hadn’t been at the Cloisters for even two weeks and already I was institutionalized.

We went to the nearest town, to Dentist O’Dowd, the dentist the Cloisters used whenever an inmate’s teeth started playing up. Which, according to Margot, happened all the time.

On the walk from the car to the surgery, I felt that everyone in the entire town was looking at me. As if I was a maximum-security prisoner who’d been released for the morning to attend his father’s funeral. I felt different, alien. They’d know, simply by looking at me, where I’d just come from.