I have two sisters, and I think siblings are always going to be irresistible for novelists. They have been throughout time and they'll continue to be.

We are all, Esme decides, just vessels through which identities pass: we are lent features, gestures, habits, then we hand them on. Nothing is our own. We begin in the world as anagrams of our antecedents.

What are you supposed to do with all the love you have for somebody if that person is no longer there? What happens to all that leftover love? Do you suppress it? Do you ignore it? Are you supposed to give it to someone else?

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.

As other authors have realized, heat can have a strange effect on us, can cause odd chemical reactions in the brain. Heat can bring out secrets; it can change people's personalities.

My husband, William Sutcliffe, the writer, is my first reader and in many ways my most important. That initial reading of the manuscript is crucial and irreplaceable and you want them to approach it as someone in a bookshop might, not knowing much about it. So I've got into this pattern of not telling Will anything about the book I'm working on. He often knows nothing about the book I'm working on at all until I give him the whole manuscript and ask him to read it. The book I'm working on at the moment he knows nothing about. No one does.

I met a retired police detective. And he said to me that the interesting thing about heatwaves, from a police perspective, is that the number of people who just walk out of their lives when the weather gets unbearable is astronomic. He said the police prepare themselves for it - for a huge rise in the instances of missing persons. People choose to disappear when it's hot. It was fascinating.