Madeleine couldn’t help offering me tea; it was a sort of ritual for her. As we sat peacefully together, she said: ‘When I left you this morning, I thought we would never see each other again.’

‘Really?’ I asked. ‘Why ever not?’

‘You have better things to do than accompany me to the other side of the world.’

‘On the contrary: that trip is the most exciting part of my project.’

‘You really think so?’

‘Yes.’

‘And your readers too?’

‘No one ever knows what will interest a reader. Maybe some of them will skip all the pages about the trip to America. But I’m sure that anyone who’s had regrets in life will relate to your desire to find that man again.’

‘Everybody has regrets, don’t they?’

‘Well, there you are: that’s a good sign. We’ll have all the depressed people on our side, and that’s a lot of people.’

Madeleine did not smile at this. There was a new seriousness about her. Her words had surprised me. How could she possibly have imagined that I wouldn’t want to go with her? She must have thought that my initial approach to her had been a sort of whim, and that she shouldn’t expect this fairy-tale-like turn in her life to continue. Well, she was wrong. Rarely had I felt so passionate about a story. I could only hail the triumph of reality. It also surprised me that Madeleine, like all my other characters, seemed so worried about whether her life would interest my readers. It was as if my publishers’ marketing director had infiltrated their minds.

I reassured them all, but in truth I had no idea what would be interesting or not for a reader. I remember a journalist who’d written a review of the first of my books to reach a wide readership: ‘This book works because it contains all the ingredients of success!’ What a strange phrase. If I’d known the ingredients of success, I would have used the recipe earlier in my career – and spared myself all those years of doing other jobs to subsidise my writing. Besides, if the ingredients of success really did exist, everyone would be able to effortlessly produce bestsellers. It was absurd. You never really know what readers will like. Reading these lines that I’m writing now, some readers will perhaps be captivated while others will be yawning with boredom. That is not my priority. Not that I am unconcerned about the reader, but what drives me above all is feeling an obsessive passion for my subject.

But I was prepared to make compromises to reassure my characters. To try to captivate the reader, I could always rely on a few tricks. I could ask you, reader, to take part in the next stage of the book. You could try, for example, to work out why Yves Grimbert had left Madeleine. That would make the story more fun and give it an obvious popular appeal.

POSSIBLE REASONSFOR YVES GRIMBERT’S DEPARTURE

– He had a false identity. And the secret services were about to unmask him.

– An incurable disease. He decided to leave rather than make the woman he loved watch him die.

– He loved another woman.

– He loved another man.

– He was involved in a crime and risked being sent to prison.

– He had a double life in the United States.

– He was a nihilist and, knowing that all stories must have an end, he preferred, as Serge Gainsbourg wrote, to flee happiness out of fear it will disappear.

– He couldn’t stand living in France any more.

– He discovered that Madeleine was in fact his sister.

– He won the lottery, but didn’t want to share the prize money.