Thriller writer Robert Crais talks to Craig Sisterson about the allure of Hollywood and turning an enigmatic sidekick into a leading man.

The very thing that drew a young Robert Crais to Los Angeles more than 30 years ago, just as thousands of people from all over the world are drawn there every year, is what makes the city such a terrific location for crime fiction, says the acclaimed novelist.

"Los Angeles is a destination city for dreamers," he says. "They're chasing hopes, chasing dreams. I don't care if they're Harvard graduates coming from the east coast because they want to be a shmancy attorney at a Century City law firm, they come for exactly the same reasons as some undocumented worker from Central America who's slipping across the river illegally. They're coming to find a future, they're coming here to build a life."

Crais, who grew up in Louisiana and fell in love with "the great promise, mystery and intrigue" of Los Angeles thanks to Raymond Chandler novels and television shows like Dragnet and Rockford Files, moved west in the 1970s because he wanted to become a writer.

"So I'm sympathetic to all those people who come chasing their dreams here, it's something we all have in common."

And it's that influx of dreamers, coupled with a canvas of spectacular physical geography painted with a colourful multicultural brush, that makes LA a perfect setting, says Crais, his passion for his adopted home clear in his voice.

"Any time you have so many people risking so much - dreamers and con men, schemers and the hopeful, the naive and the creative - any time you have so many dreams bumping up against each other, so many people taking risks on themselves, it's an ideal place for desperation and crime."

Unlike many newcomers whose hopes end up dashed on Hollywood's "boulevard of broken dreams", 55-year-old Crais has found plenty of success, first as an Emmy-nominated TV writer for shows like Cagney and Lacey, Hill Street Blues and Miami Vice, then as a best-selling author.

His 17th novel, The Sentry, has just been released. It's an action-packed tale centred on enigmatic former LAPD cop and mercenary Joe Pike, who is driven to protect a Hurricane Katrina refugee and her uncle from a vicious gang, only to stumble into something far larger and more sinister.

The book is not only the latest instalment in Crais' popular Elvis Cole and Joe Pike series, but a continued evolution in his writing from the early days of "lighter" private eye tales starring wisecracking semi-goofball Cole, with sunglasses-wearing Pike making helpful but violent cameos, to a darker, layered style, with the dynamic duo's roles flipped and the stoic tattooed sidekick becoming the leading man.

"Perhaps the single most difficult aspect of writing this novel or any of the more recent novels is walking that very fine line between maintaining Pike's enigmatic nature - that I think is mandatory. It's who he is, it's what my readers enjoy, it's what I enjoy - but at the same time I want to make him a fully realised human being," says Crais.

"To learn, to discover what's behind his sunglasses, what's under all the impenetrable armour he carries, I find fascinating. But I can't reveal too much of it, he has to remain a mystery, has to remain an iceberg where, whatever it is you see, there's so much more beneath the surface. That's a very fine line to walk, and I'm constantly doing a balancing act as I write every scene."

Crais says that although Pike seems to keep himself isolated from the world, hidden behind his sunglasses and non-expressive face, over the course of the series it's clear that "human connection is important to Joe".

In fact, the friendship between Pike and Cole is the soul of a series that on the surface seems focused on page-turning action and intrigue.

"Joe's not going to have a bunch of buddies he goes bowling with, that's not Joe, but clearly that friendship, that human connection he has with Elvis, is extremely important to him. Look at the loyalty they have, the devotion to each other. Look at how much they trust each other."

It was that sense of Pike being open to human connection that inspired The Sentry. Crais began to play with notions of Pike eventually wanting a woman in his life. "I wanted to open that particular door for Joe so I could see what that would mean, and that's when I started thinking about what would amount to a Joe Pike romance - a romance totally unlike any other romance," he says, laughing. "What would be a romance for Joe, built my kind of way - which of course means high body count, lots of kicking ass."

Crais credits his early Hollywood days working with and learning from "some enormously talented people" in television, such as Hill Street Blues creator Steven Bochco, for his understanding of action-packed storytelling. "My TV years were my writing school," he says. "When I now to this day read reviewers who note the visual nature of my work or the tightness of the plot or the fact that you can't stop turning the pages, these are things that I took with me from TV."

But in the end, storytelling is about character, says Crais. "I like stories about human beings. The reality is that, at least to me, is that people - me, you, the people we know, the people we meet - we're the mystery. It has nothing to do with who stole the Maltese Falcon or the stash of money. The true mystery is who we are as human beings, how are we going to react in a certain situation.The woman you love, does she really love you? When your son or daughter tells you something, are they telling you the truth? What's the real secret they're keeping?"

It's those kind of human mysteries which Crais believes "bind us together".

"In a situation with a character like Elvis or Joe, I think there's great storytelling to be had if you delve into who they are as people. Don't simply accept Joe Pike as a thug with sunglasses and tattoos on his arms. He's more than that. There's actually a lesson there in the book - is Elvis Cole simply a guy with a fast one-liner and a loud shirt on?

"No, he's more than that, just like I'm more than a guy who types, just as you are more than a guy who types. We all have our lives, and I think when people make snap judgments about anyone else, it's easy to pigeonhole, it's easy to be biased and bigoted, it's easy to be wrong.

"I think the deeper you look into other characters and other people, when you take a moment and peel back the layers and look at what's really beneath them, and the reasons for the way they are the way they are, people become endlessly fascinating.

"Everyone has a story to tell, and as a storyteller I'm interested in finding those stories and telling them."

The Sentry (Orion $39.99) is out now.