I watched her eyes flash back to her childhood. To her own terror of that carbon monoxide filtering through the air conditioning and she and her brother not running into their parents’ room saying they felt unwell. I knew I’d hit home. Knew she’d have covered guilt with her grief counsellor many times. I licked my lips and prepared to act like I’d never acted before. I adopted a tone of kind, caring concern.

‘Amanda, I’m worried about you. I’m worried that some of your therapy sessions, particularly the group ones, encourage an over-active imagination. You’ve been exhibiting it a lot recently. Remember when you thought Colin and Trevor, in the flat below, were plotting against you? Taking your mail? And when you thought the Amazon man was spying through your letter box? I’m wondering if you should go back to your GP. Change your medication, even?’

Oh, if she could be manipulative, I could too. And I knew that her favourite topic, herself and her complicated medical programme, was the surest way to her egotistical heart.

‘There’s nothing wrong with my medication,’ she snapped. ‘I went to Austria in January, to the Holen, and was entirely irrigated of toxins, so that everything I take now has a better chance. And don’t try to—’

‘The Holen Clinic?’ I interrupted sharply. ‘Isn’t that the one that’s just been discredited? By some neuroscientist from Columbia University?’

It was the detail that got her. Not entirely invented, either, I’d skimmed an article a while back.

‘Columbia …?’

‘Yes, it was in The Times. Apparently, the Holen’s irrigation methods are highly suspect and there’s a lot of controversy about it. I knew you were a patient so I followed it up online, in the Medical Journal.’

‘I don’t read – I didn’t see—’

‘No, you wouldn’t, because it’s encrypted. You can only get access if you’re registered, which a friend of mine is. Hilary, a psychologist. I asked her about it. And obviously I didn’t want to worry you. But since you’ve mentioned it …’

‘Could she get me the report?’

Gotcha. ‘I’ll ask her. I’m seeing her soon.’ I know of no one called Hilary. No psychologist.

The bill arrived and I quickly got my card out, indicating to the waitress I’d like to settle it now. She disappeared for her machine.

‘Yes, because the Belgravia Clinic, where I go for my irrigation in London, are also setting up in Austria and are keen for me to go there, and when I said I’d been going to the Holen for years, they did actually raise their eyebrows … I thought they were just touting for business. It’s just so hard to believe. The Holen is so well established …’