Now, this isn't something I normally do, but I contacted the estate of Upton Sinclair and bought the film rights to the book. Before I became a journalist I worked for an independent film company in New York, and I thought that when I finished the book I was writing I would try to get "Oil!" made into a movie. What I really wanted to do was find a director who felt as passionately about the book as I did. Oddly enough, what happened was the director found me. It turned out that Paul Thomas Anderson had found a copy of the novel in a used bookstore in London, and become obsessed with it and its themes, much the same way I had. He got in touch with me and told me he really wanted to do a film inspired by the book.

To be honest, at first, I wasn't sure he was the right guy for the job, which shows how smart I am. But then he came up to see me, and we spent a couple of days together, and I realized that he was the real deal, absolutely brilliant, a real artist. He had a bold and original vision of how to tell this story. He felt intensely passionate about the material. So I decided he should do it. That's how I became executive producer.

'Los Angeles Was the Kuwait of the Jazz Age'

Q. "Oil!" takes place about a decade or so later than the movie and, at 548 pages, sprawls over practically every social and economic trend of the era, from California's new car-crazed culture to face lifts to the factional battles of America's "reds." But the heart of it is a detailed chronicle of the Southern California oil boom. How would you summarize how all these themes fit together?

A. The novel is epic in scope, and it's really about the day and age in which Sinclair was living, the society of Southern California in the 1920s. George Bernard Shaw regarded Sinclair as the great historian of his era, who managed to capture the essence of the times in his novels.

Los Angeles during the 1920s was a laboratory of the future. It was the first city created to serve the needs of the automobile — it's where the car culture was born. And for a brief period, it was the center of world oil production. A handful of major discoveries — at Huntington Beach, at Signal Hill near Long Beach, at Telegraph Hill and Santa Fe Springs in Orange County— made Southern California the world's biggest oil producer. The oil industry became the leading sector of the California economy, and the state was soon responsible for about a quarter of the world's supply.