“YOU’RE THE competition,” says David Mamet when I arrive in his hotel room.

He’s referring to the fact that he writes a monthly column for another newspaper, which is no surprise as he is known for his ferocious work ethic. So while he’s here in Los Angeles to talk about his latest film, Spartan, he has also been commuting to San Francisco, where his reinterpretation of Dr Faustus had its world premiere in March. Does he ever stop? “I like working. Noël Coward said, ‘Work is more fun than fun’,” says Mamet, who speaks as he writes, in terse, punchy sentences.

Short and burly, with a gruff voice and a greying crew cut and big glasses, Mamet can be disconcerting in his directness. He’s a confirmed Anglophile who is married to the British actress Rebecca Pidgeon and cites Harold Pinter as his hero. But he is hardly forthcoming and claims to have little interest in discussing his life as a playwright and film-maker. “I like analysing the work sufficiently to do it. After that, I couldn’t care less.”

Spartan is the ninth film he has directed as well as written, the first was 1987’s House of Games and like all his previous movies it’s set in a hermetic world where the characters speak a language all of their own. This time Val Kilmer’s special forces operative is caught up in a conspiracy with its roots in the White House, as he tries to rescue the President’s missing daughter.

The film presents an unflattering portrait of the men and women who run the United States and, combined with a strong performance from Kilmer that is as unexpected as it is effective, it gives Spartan a resonance that makes up for the disappointment of Mamet’s last movie, Heist (2001).

“I’m deeply cynical about any occupants of the White House, real or imaginary. One must assume that, being human, they’re going to make the mistakes that the rest of the world makes, and then some other ones too.”

Does he think the current administration is worse than previous ones? “Oh, ask me again in December.”

He is backing John Kerry to beat Bush in the forthcoming election. “I just think he’s going to win. I won’t talk about my own politics, but I think the American people are going to think it’s time for a change.”

Current affairs are not a Mamet speciality. His real themes are the venal nature of American society, as shown in Glengarry Glen Ross, his Pulitzer prize-winning piece about crooked real estate agents, and sexual politics, which he explored controversially in Oleanna (1992).

His finest work, the plays Glengarry Glen Ross and Sexual Perversity in Chicago and the films State and Main and The Spanish Prisoner, has its roots in his own experiences. After college in Vermont, where he met his regular collaborator William H. Macy, Mamet drifted around the seamy side of his native Chicago for a while. It’s the reason why there are so many villains in his work and why he is a master of the vernacular.

“I knew a lot of criminals when I was a young man and impressionable,” Mamet says. “I spent a lot of time listening to the way they spoke. I was a cab driver for a while, I washed windows, I worked in a fraudulent land-sales organisation and I played a lot of poker. I spent a lot of time in pool halls and gambling parlours.”

Was he a good hustler? “I was a pretty good poker player. I couldn’t shoot pool worth a damn.”

It was a macho world and his work reflects that, but Mamet bristles when asked about his supposed lack of empathy for his female characters. “I feel pretty comfortable writing about women. Before Dr Faustus, the last play I did was Boston Marriage, which was about a lesbian love affair.”

It earned him an Olivier nomination after it was put on at the Donmar in 2001, although it’s not classic Mamet.

Mamet was a failed actor when he started his own theatre group in the early Seventies, and began to teach writing. “All you need is a moderate grasp of the subject and a great line of bull. Sometimes you don’t even need the first thing at all,” he grins.

But even while he was America’s hottest playwright, he had his eye on Hollywood. He made his screenwriting debut with the 1981 remake of the noir classic The Postman Always Rings Twice.

Now he spends more time writing scripts than plays. “It’s because the urban landscape has changed. You need a stable audience to have a flourishing theatre and the theatregoing audience lives in the suburbs now.”

Isn’t that frustrating for him? “A little bit, but it’s the time in which I live.”

Despite some bad experiences, he loves making movies. In part, that’s because directing is so different from the solitary life of a writer. “It’s great. It’s like going on safari.”

How, though, does Mamet, who used to fine his students if they turned up late to class, cope with the pressure from the collection of chancers, amateurs and egomaniacs who populate Hollywood? “I don’t care about them. The only pressure I feel is to do the best job I can. The fact that there’s some person trying to make the pressure worse is kind of a joke. So what? I’m going to enjoy myself.”

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