I think all families have these secrets, and it's sometimes the strangest things that bring them out. That was part of my interest in the heatwave, in heat as a catalyst for uncovering truths. I was reading Alice in Wonderland to one of my kids recently, and I remembered that it starts on a really hot day. Alice falls asleep because of the heat; the whole story is predicated on falling into a heat-fueled dream.

Listen. The trees in this story are stirring, trembling, readjusting themselves. A breeze is coming in gusts off the sea, and it is almost as if the trees know, in their restlessness, in their head-tossing impatience, that something is about to happen.

Spending a lot of time away from home was strange. My parents visited me, obviously, but I was in hospital a lot, alone. And then when my health had improved a bit and I was in a sick-bed in the house, with the life of the house going on around me, that was very vivid for me. I always think that's a bit like the position of a novelist in a novel, going through drafts: there but not there, one remove from reality.

We all have a family, whether we like it or not; we all come from somewhere, and there's something strange in the way you have, with siblings, two or three personalities yoked together for life. You grow up thinking those family relationships are set in stone and then you get older and realize they're not. They're always shifting.

When I worked at The Independent newspaper, I had colleagues who would laugh and say that whenever they picked up the phone to my dad and heard his accent, they thought they were about to hear a five-minute warning to get out the building. People in Britain have always thought it acceptable to make racist remarks about the Irish. The prejudice underlying that supposed joke was everywhere.

When my family moved from Ireland in the 70s, Britain was such a difficult place to be Irish. It was a decade of real social and economic upheaval in Britain. There were strikes, the three-day week, the oil crises, huge inflation, the winter of discontent and, what was it, four Prime Ministers? And relations between Britain and Ireland at that time were at an all-time low. I was born in the year of Bloody Sunday and of course the pub bombings happened in the mid-1970s.

People had tell me the most personal things. People I'd never met before would say thing like "Oh, that was the summer I had an affair with my neighbor." The 1976 heatwave occupies a peculiar place in people's psyches.