I’d made up a reason why I needed the car that day – claiming I wanted to drive to the big DIY superstore in the next town. Anya had a work event and wouldn’t be home early, so I had plenty of time to drive to Cambridge.

I’d never been there before. I think I must have been expecting to see some dreaming spires as I followed the satnav route from the M11, but I was directed around the northern edge of the city, past suburbs that looked much like anywhere else. If I had ever given Cambridge University any thought at all, I pictured the likes of Sebastian Flyte, all cricket jumpers, teddy bears, and lying around on mint-green grass in the sunshine. But because Anya had given it up and gone on to Durham, she spoke about it almost never.

Irene lived in a northern suburb of the city called King’s Hedges, just down the road from a driving range and a couple of tech company premises, in a neat bungalow with hanging baskets outside that looked dry and neglected.

She was staring at me now, chewing her bottom lip. I was conscious of towering over her. I kept well back from the front door and attempted to radiate as much friendliness as I could, in the circumstances.

‘If you like,’ I said, ‘I could maybe buy you a cup of tea or coffee if you want to go to a café?’

She looked at me as though I had made the most ridiculous suggestion she had ever heard before replying. She wore no make-up and her curly, iron-grey hair was short and cut in a no-nonsense style.

‘Why would we pay for tea when I have perfectly good tea inside?’ she said and then beckoned me in.

‘Go on through,’ she said. ‘But I want you to know that my friend Rowan is just next door and she will call the police if she thinks I am in any trouble.’

Her voice shook a little as she said this and it made me feel even worse about what I was doing here.

‘I promise you,’ I said as I went into a living room filled with patterned sofas and smelling of pot-pourri, ‘I wouldn’t dream of causing you any trouble. I just want to talk, that’s all.’

She made a harrumphing sort of noise and then said, ‘Tea?’ in a way that didn’t brook much disagreement.

I thanked her and sat down as instructed.

The stone mantelpiece contained a number of photographs and I got up again and quietly went over to have a look. There were two school photographs of the kind my school no longer went in for, preferring instead to attempt arty shots of pupils in groups. One showed a boy with dark red hair, grinning cutely at the camera with two missing teeth. This was obviously the younger son, the one in the picture with Anya.