I began writing fiction because it was the only way to tell all the intricacies of a real-life spy story. I had written a front-page piece for the Wall Street Journal in 1983 about how the CIA had recruited Yasser Arafat's intelligence chief during the '70s. After the story was published, I learned through a strange chain of events the inner details of the operation—including the names of people who were still at risk. I decided that the best way to narrate what I knew was in a novel. It was published in 1987 by W.W. Norton as Agents of Innocence and is still in print.

It's harder to explain why I continued writing fiction. Since that first book I've written seven more, and my latest, Bloodmoney, will be published by Norton in June. It's not that I lack other chances to write. My day job is journalism, and I have been writing a column for the Washington Post since the late 1990s. So why fiction, too?

The simple answer is that it's pleasurable. As so many writers know, the experience of creating an imaginary world is closer to dreaming than it is to normal, grit-your-teeth work. It's preconscious, rather than conscious. Ideas fall into your head, and the book writes you, rather than the other way around. This experience of getting so lost in my writing that I lose track of time, or of anything outside the imagined world, is a release for me.

It's fun. And to be honest, it has helped pay my children's college tuitions.

My spy novels have all been drawn from the world of fact, just as the first one was. Body of Lies, which later became a movie starring Leonardo DiCaprio, was based on extensive conversations with the head of the Jordanian intelligence service, who was the model for my character, "Hani Salaam." I wrote my next book, The Increment, after visiting Iran and studying its nuclear program. People who read my account of electronic sabotage of Iranian nuclear systems teasingly asked me if I had any connection with the Stuxnet virus. Of course not, but I knew that Iran's vulnerability was in the supply chain supporting its clandestine nuclear program.

The same reporting process took place with my latest novel, Bloodmoney. I've traveled half a dozen times to Pakistan over the past two years, including jaunts to South Waziristan and other tribal areas. I spent many hours in Islamabad with officials of Pakistan's spy agency, the fearsome Inter-Services Intelligence (ISI). And I watched the ISI's tricky game with the CIA. That factual background was a platform for the book.

And as sometimes happens, real life ended up bizarrely mirroring some themes of the novel, in the recent Raymond Davis case—a busted CIA operation in Pakistan that was resolved by payment of "blood money." But for more on that connection, you'll have to read the book.

David Ignatius, a prize-winning columnist for the Washington Post, has covered the CIA and the Middle East for many years. His Body of Lies and The Increment were bestsellers.

David Ignatius, a prize-winning columnist for the Washington Post, has covered the CIA and the Middle East for many years. His Body of Lies and The Increment were bestsellers.