‘It’s a girls’ boarding school in Surrey. I’ve only heard of it because I happened to grow up in the next village,’ said Jan, a hint of apology in her voice. ‘Mary went to school with diamond heiresses and the daughters of film stars. Seriously.’

‘Her family are rich?’ Charlie pictured 15 Megson Crescent, its peeling wallpaper and blackened carpets.

Jan laughed. ‘They must be if they sent her to Villiers. She told me the fees were around fifteen grand a year when she went, and that was years ago. A lot of her friends were called “The Hon” this or that. Mary said most of them were thick, but then she never seemed to rate anyone’s intellect very highly.’

‘Did you ever see any of her other pictures, apart from the ones she brought in for you to frame? When I was at her house I saw some unframed ones she’d put up on the walls—of a family who used to live on the estate, I think.’

Jan looked puzzled. ‘Mary was obsessive about framing her work. She didn’t regard a picture as finished until it was framed. She used to hassle me mercilessly, wanting everything framed straight away. It was almost as if . . .’

‘What?’

‘I don’t know. As if she didn’t think they were safe until they were behind glass, or something. Or as if she didn’t think they counted, somehow. Are you sure the unframed pictures you saw were hers?’

‘Positive.’

‘How odd.’ Jan rubbed her collarbone, thinking. ‘I’m not saying you’re wrong—Mary’s style’s unmistakeable—but I can’t understand it. It’s just not Mary to leave her work unframed.’ She peered into her empty mug. ‘Another tea?’

‘No, thanks,’ said Charlie. ‘I’d best be off in a minute.’ She didn’t know how to ask about the Access 2 Art fair without sounding as if she was trying to catch Jan out: I know someone who says you lied. ‘I take it you no longer frame for Mary,’ she said eventually. ‘What went wrong?’

‘Two things, and they happened in quick succession. Mary painted something I hated—something I objected to, actually—and I couldn’t pretend to feel otherwise about it. She took exception. I still framed it for her, but that wasn’t good enough. She was used to me raving about the brilliance of everything she did—the last thing she expected was disapproval, but I honestly couldn’t help it.’

‘How come?’