The door opens and she walks in. ‘Late breakfast,’ she says. ‘Actually, it can double as late lunch.’ She’s wearing a grey T-shirt with blue paisley pyjama bottoms and carrying a large blue cloth-bound hardback book. Horizontally, in both hands. Balanced on top is a teapot trailing a green label on a piece of string, a cup, and a sandwich overhanging the edges of a saucer that’s too small for it. ‘I’m hoping it’s not every day someone brings you peppermint tea and a Marmite sandwich on a tray. Well, a book,’ she corrects herself. In the pocket of her pyjama bottoms I can see the outline of her cigarette packet.

Something has changed. I’m not scared of her any more.

Pieces of last night start to come back to me: Mary’s insistence that she couldn’t tell me; she had to show me. She didn’t want to talk while she drove, so we listened to the radio for a while. Then she put a CD on; the ‘Survivor’ song started to play. ‘Martha was playing this when she hanged herself,’ Mary said matter-of-factly. ‘Odd choice, don’t you think? If you’re going to commit suicide, why play a song that’s all about coping without somebody, growing wiser and smarter and stronger?’

‘Maybe . . .’ That was as much as I could say. I didn’t feel comfortable speculating.

‘Irony, do you think? I don’t think so. Arrogance: that’s what I think it was.’

I asked her what she meant, but she frowned and shook her head. ‘Not tonight,’ she said. ‘Not if you want me to get us there intact.’ Then she took her mobile phone out of the glove compartment, saying she had to ring Villiers. She asked for someone called Claire. I listened as she ordered her to contact the local police, to meet us and them at Garstead Cottage in two hours’ time.

‘Why the police?’ I asked.

‘It’s my routine,’ said Mary, turning up the volume on the stereo so that I couldn’t say anything else.

As we pulled in through the school’s large sculpted iron gates, the police car was ahead of us. Claire Draisey, who turned out to be Villiers’ Director of Boarding, was waiting for us next to the side door of Garstead Cottage, taking shelter from the drizzle in a partially covered wooden outbuilding that was attached to the house. In it were two old bicycles, a watering can and a large cardboard cut-out of a cow in profile, a cow wearing a yellow earring. I didn’t register the oddness of this until later; at the time, it seemed one of the less odd aspects of the situation.