Adam Sisman published his first, definitive, biography of John le Carré (AKA David Cornwell) in 2015. The book was produced with access to the author and his archive but there were aspects of his life that le Carré refused to discuss, particularly his numerous extramarital affairs. He suggested to Sisman the “worst and maddest” aspects of his behaviour be kept for a second volume. Nearly three years on from the death of le Carré – and that of his second wife, Jane – Sisman (also the award-winning author of books about historians AJP Taylor and Hugh Trevor-Roper) has written The Secret Life of John le Carré.
Did you always imagine that this material would become a second book?
Originally, I thought in terms of doing an updated version of the original book. I’m now very pleased that I’ve made it a separate book. Because I think it enabled me to do things that I wouldn’t otherwise have been able to do. It obviously includes things I wasn’t able to write about while David was still alive. But there’s also the story of the negotiations involved in writing the book and our relations during that.
How easy was it to discover these secrets?
One of the ironies is that, at the beginning, I didn’t think that these infidelities were very important. But then I just kept coming across them wherever I went. I remember going out to lunch with some friends and there were some other guests there, and they said: “Oh, we know Verity Mosley, and she talks about the affair with David.” And then I was at a party talking to someone I just met and when I mentioned my book he said: “Oh, I’ve got a friend whose mother had an affair with him.” It just kept popping up. Two more have surfaced since I finished.
Do you think he would have approved of all this coming out?
I find it a very difficult question to answer. He said he didn’t care what I wrote when he was dead. Maybe I should take him at his word. On the other hand, I did learn with David never to do that.
It’s fascinating to read his letters to you, alongside his letters to his lovers; they have the same kind of complicated flirtatious tone. They must have been extraordinary things to receive…
The writer Nicholas Shakespeare, who was his friend, told me: “It didn’t matter whether you’re a man or woman or an ocelot, he had to seduce you.” I felt that he wanted to make me love him. Not sexually. But that was just his default position. When he was turning it on, he was the best company of anyone I’ve ever met. But I’d constantly pinch myself and say: we’re not really friends. And, actually, as soon as I turned my back, I knew he was going to say something rude about me. One of his least attractive qualities was his tendency to denigrate everybody: his agent, his editor, his friends, his children.
One of his hopes for the project seemed to be that it might explain him to his children – in a way that he never understood his own father, Ronnie [an infamous conman and womaniser who served time in prison for fraud].
Absolutely. In his most autobiographical novel, A Perfect Spy, the character based on himself, Magnus Pym, talks about his father being a very bad man, who ruined people’s lives. Pym addresses his own son to say: “I’m the bridge that you must walk over to have a happy, fulfilled life.”
You express at the end your hope that what you have revealed about his life shouldn’t damage his work. Were there any elements of his behaviour that could be seen as predatory?
I didn’t see him as predatory. He didn’t talk about women in that way. I think he often imagined himself in love, but almost as soon as that love was reciprocated, he would turn his back. He had real problems with affection. He definitely did treat many of his lovers poorly, and his wives pretty terribly.
His belief seemed to be that he needed all this complexity to be creative, a different muse for every book. Were you persuaded by that?
I think he was addicted to jeopardy and to risk taking. He liked to be on the brink of exposure, but he would have been dismayed to have been completely found out.
You discuss Janet Malcolm in passing in the book, on writer’s ethics. I often think about her famous quote that every journalist knows what they’re doing is morally indefensible. Do you think biography necessarily involves similar compromises?
I don’t agree with her. I think responsible journalism is essential. With biography, there are always moral qualms. I mean, I had this very uncomfortable interview that I describe in the book with David’s wife, Jane, which he orchestrated for us to discuss his infidelity. I felt that we were two puppets being set up by this man who had gone off for a walk on Hampstead Heath.
Are there books that you’ve been inspired by, that inform such questions?
I’m always reading new biographies – and books about writing them. This morning I was reading Robert Caro’s book Working, a sort of interim memoir, which is full of fascinating stuff. The book that was most influential for me was Richard Holmes’s Dr Johnson and Mr Savage, which freed me from some boring ideas I had for a book about Boswell and made me think about biography in a different way.
Do you have a kind of hitlist of future subjects?
Yes. But I’m not about to tell you who is on it.
What books do you have by your bedside?
The two I’m most actively reading at the moment are Gerald Brenan’s South from Granada, and John Maynard Keynes’s The Economic Consequences of the Peace – In Our Time devoted an episode to it the other day so I thought I better read it.
• The Secret Life of John le Carré by Adam Sisman is published by Profile (£16.99). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply
