I realized he was looking for an excuse not to go. ‘I’ll do it,’ I said. ‘If Will tells me what to do. I don’t mind staying to help.’ I said it almost before I realized what I was agreeing to.

‘Well, that’s something for us both to look forward to,’ Will said grumpily, after his mother had left. ‘You get a good view of my backside, and I get a bed bath from someone who falls over at the sight of naked flesh.’

‘I do not fall over at the sight of naked flesh.’

‘Clark, I’ve never seen anyone more uncomfortable with a human body than you. You act like it’s something radioactive.’

‘Let your mum do it, then,’ I snapped back.

‘Yes, because that makes the whole idea of going out so much more attractive.’

And then there was the wardrobe problem. I didn’t know what to wear.

I had worn the wrong thing to the races. How could I be sure I wouldn’t do so again? I asked Will what would be best, and he looked at me as if I were mad. ‘The lights will be down,’ he explained. ‘Nobody will be looking at you. They’ll be focused on the music.’

‘You know nothing about women,’ I said.

I brought four different outfits to work with me in the end, hauling them all on to the bus in my Dad’s ancient suit carrier. It was the only way I could convince myself to go at all.

Nathan arrived for the teatime shift at 5.30pm, and while he saw to Will I disappeared into the bathroom to get ready. First I put on what I thought of as my ‘artistic’ outfit, a green smock dress with huge amber beads stitched into it. I imagined the kind of people who went to concerts might be quite arty and flamboyant. Will and Nathan both stared at me as I entered the living room.

‘No,’ said Will, flatly.

‘That looks like something my mum would wear,’ said Nathan.

‘You never told me your mum was Nana Mouskouri,’ Will said.

I could hear them both chuckling as I disappeared back into the bathroom.

The second outfit was a very severe black dress, cut on the bias and stitched with white collar and cuffs, which I had made myself. It looked, I thought, both chic and Parisian.

‘You look like you’re about to serve the ice creams,’ Will said.

‘Aw, mate, but you’d make a great maid,’ Nathan said, approvingly. ‘Feel free to wear that one in the daytime. Really.’

‘You’ll be asking her to dust the skirting next.’

‘It is a bit dusty, now you mention it.’

‘You,’ I said, ‘are both going to get Mr Muscle in your tea tomorrow.’

I discarded outfit number three – a pair of yellow wide-legged trousers – already anticipating Will’s Rupert Bear references, and instead put on my fourth option, a vintage dress in dark-red satin. It was made for a more frugal generation and I always had to say a secret prayer that the zip would make it up past my waist, but it gave me the outline of a 1950s starlet, and it was a ‘results’ dress, one of those outfits you couldn’t help but feel good in. I put a silver bolero over my shoulders, tied a grey silk scarf around my neck, to cover up my cleavage, applied some matching lipstick, and then stepped into the living room.

‘Ka-pow,’ said Nathan, admiringly.

Will’s eyes travelled up and down my dress. It was only then that I realized he had changed into a shirt and suit jacket. Clean-shaven, and with his trimmed hair, he looked surprisingly handsome. I couldn’t help but smile at the sight of him. It wasn’t so much how he looked; it was the fact that he had made the effort.

‘That’s the one,’ he said. His voice was expressionless and oddly measured. And as I reached down to adjust my neckline, he said, ‘But lose the jacket.’

He was right. I had known it wasn’t quite right. I took it off, folded it carefully and laid it on the back of the chair.

‘And the scarf.’

My hand shot to my neck. ‘The scarf? Why?’

‘It doesn’t go. And you look like you’re trying to hide something behind it.’

‘But I’m … well, I’m all cleavage otherwise.’

‘So?’ he shrugged. ‘Look, Clark, if you’re going to wear a dress like that you need to wear it with confidence. You need to fill it mentally as well as physically.’

‘Only you, Will Traynor, could tell a woman how to wear a bloody dress.’

But I took the scarf off.

Nathan went to pack Will’s bag. I was working out what I could add about how patronizing he was, when I turned and saw that he was still looking at me.

‘You look great, Clark,’ he said, quietly. ‘Really.’

With ordinary people – what Camilla Traynor would probably call ‘working-class’ people – I had observed a few basic routines, as far as Will was concerned. Most would stare. A few might smile sympathetically, express sympathy, or ask me in a kind of stage whisper what had happened. I was often tempted to respond, ‘Unfortunate falling-out with MI6,’ just to see their reaction, but I never did.

Here’s the thing about middle-class people. They pretend not to look, but they do. They were too polite to actually stare. Instead, they did this weird thing of catching sight of Will in their field of vision and then determinedly not looking at him. Until he’d gone past, at which point their gaze would flicker towards him, even while they remained in conversation with someone else. They wouldn’t talk about him, though. Because that would be rude.

As we moved through the foyer of the Symphony Hall, where clusters of smart people stood with handbags and programmes in one hand, gin and tonics in the other, I saw this response pass through them in a gentle ripple which followed us to the stalls. I don’t know if Will noticed it. Sometimes I thought the only way he could deal with it was to pretend he could see none of it.

We sat down, the only two people at the front in the centre block of seats. To our right there was another man in a wheelchair, chatting cheerfully to two women who flanked him. I watched them, hoping that Will would notice them too. But he stared ahead, his head dipped into his shoulders, as if he were trying to become invisible.

This isn’t going to work, a little voice said.

‘Do you need anything?’ I whispered.

‘No,’ he shook his head. He swallowed. ‘Actually, yes. Something’s digging into my collar.’