VIKRAM CHANDRA does not look like someone who hangs out with gangsters. Yet for the past seven years, the diminutive novelist has spent a lot of time with some very bad people. He has met men who killed for a living and others who just extorted and tortured people for not "forking out." And he has been driven around in circles meant to disguise his whereabouts before being rushed to secret hideouts.

"I remember one night I went out for beers with some of these shooters," said the 44-year-old novelist while on a recent visit to New York, "and I thought to myself, 'Gosh, I could almost be friends with these guys. They're really nice guys.' And then I realized they probably would go out later that night and maybe kill someone."

Chandra wasn't doing this for kicks. For the past decade he has been working on a big novel, and at last it's here. Sacred Games tells the story of a crime boss and a Sikh police inspector and the way their lives connect in the Indian megalopolis Mumbai (a.k.a. Bombay) and beyond during the 1980s and '90s. It is a brilliant earthmover of a book—Crime and Punishment crossed with The Godfather, with some Sopranos-inspired irony thrown in.

It has made Chandra famous back home in India. "Every time there is a shooting in Bombay now, someone asks me to come on air and talk about it. Last time it happened, I said, 'Well, I'm not really an expert about this.' And the newscaster said, 'That's OK. Can you come on anyway?'"

In the '80s, the influence of organized crime in Bombay became so extensive, it could affect elections. Then in the '90s, gang bloodbaths became visible to all. "You would open the newspaper, and there would be four dead in a shoot-out," Chandra says. "The next day, it would be six. It was like a cricket score every morning." Middle-class citizens were not just witnesses; they became targets, too.

"Doctors I knew would get a phone call saying, you know, we want this much money, more or less, to let you live," he says.

Around the time his brother-in-law, a film producer, hired bodyguards, Chandra figured he should start writing about the subject. He banged out a short story about a middle-aged, lovelorn Sikh police inspector named Sartaj Singh. It was published in his 1997 collection Love and Longing in Bombay, but it didn't satisfy his interest.

"I started to get to know about policing in India, more than I needed to know as a citizen. And I started to hang out with policemen, became friends with a couple of them, and the character in that story just wouldn't leave me alone. I felt like we had unfinished business."

So he threw himself into writing a short book. "I thought of it as one of those thrillers where you find a dead body in the water, and 200 pages later, it's all explained." But each time he pulled a thread, another would unravel. And what had felt like a local phenomenon proved to cut across India, the whole subcontinent, encapsulating even the current geopolitical situation and the so-called war on terror.

"Intelligence agencies like to use these criminal organizations for logistical support," Chandra explains. "These guys operate as an extra constitutional arm, so the government can always deny responsibility if someone gets busted doing something that they shouldn't. But they become cyborgs of a sort that no one can control. The militant movements will sometimes obtain arms from these organized-crime gangs, who have business with gun-running. And then these guys will get in Afghanistan and Pakistan heroin, which then brings in new revenue. It's a very incestuous, naughty triangle."

One of the most bizarre twists is that many of India's biggest crime bosses reach into the film world, where they can control or influence their own mythologizing. In Sacred Games, the book's key gangster, Gaitonde, works his way into the heart of Bollywood, where he cleans up dirty money. It sounds improbable, but, as with much in this book, it's drawn from life.

A few years ago, a movie about the gang world won a prominent award, Chandra says. "The day the award was announced, this guy walks on stage to accept, and everyone realizes he's the brother of one of the biggest bosses, right? So his representation was basically about his life."

Chandra grew up in the Bollywood film world, so it didn't take much research for him to imagine his way into it. His mother is a scriptwriter, his aforementioned brother-in-law a producer, one sister is a director, the other a film critic. Chandra dabbled as well, co-writing Mission Kashmir, a drama about a police officer who adopts the son of a man he kills while pursuing a terrorist.

As much as he seemed destined to flicker at the edge of the cinematic world, Chandra never expected to be fully immersed in it. He attended film school at Columbia University in New York and dropped out to write his first novel, Red Earth and Pouring Rain, published in 1995 when he was 33, after which he spent time as a computer programmer and software consultant.

Sacred Games has effectively put an end to any such moonlighting. The book sold for more than $1 million in the United States, and for a hefty six-figure sum in England; still not enough for Chandra to buy a decent home in California, but enough to give him some breathing room.

Now he lives a global existence, dividing his time between India and Berkeley, where he teaches literature and lives with his wife. The juxtaposition of his two worlds doesn't create much friction for him, since where, when and how cultures overlap has always been his obsession.

"One amazing thing about Bombay is how everything is so wrapped together and on top of each other," Chandra says, sounding every bit like the city's booster, even if his book might make some tourists think twice about visiting. "So you have an expensive posh suburb where it is extraordinarily expensive right next to a slum."

"A lot of the younger front-line shooters of the organized-crime people are not the poorest of the poor," he continues. "They are lower-middle-class boys who maybe have a bit of a college education. The gang guys are really smart, they come up to them and they say, 'OK, I'm going to give you a motorcycle and 10,000 rupees a month. And if you work hard and are loyal, you might one day own a fleet of Mercedes.'"

The abject poverty that one thinks generates crime, he says, is not necessarily the only dynamic at work. As Sacred Games reveals so stunningly, there is much, much more at play.

Sacred Games by Vikram Chandra; HarperCollins; 928 pages; $27.95 cloth. John Freeman is president of the National Book Critics Circle.

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