"I would always consider myself a novelist," the affable British writer said during an interview this week to promote his latest page-turner, "The Fear Index."

"I'd sooner be the captain of my own leaking tugboat than third mate on an ocean-going luxury liner. You know, I'm responsible for one, I can do everything. Whereas the other, in the end you're called up by the captain onto the bridge .... and just given your instructions."

Harris, of course, is partly joking about the many-headed behemoth that is filmmaking (he says he likes the "discipline of doing movies"), but the comment also speaks to his massive success authoring some strikingly imaginative fiction (he's produced eight novels).

Power has been a recurring theme.

Harris's debut novel, 1992's "Fatherland," looked at what might have happened had Nazi Germany won World War Two. He's since tackled ancient Rome with "Pompeii" and the first two instalments of a trilogy on the life of Cicero - "Imperium" and "Lustrum." And, he's delved into modern-day British politics with "The Ghost" (made into Polanski's "Ghost Writer").

Writing about the world of finance in "The Fear Index" seemed like a natural step.

"There's nothing more powerful in the world than the financial markets," said Harris, 54.

"The Fear Index" draws its title from the volatility index, or "VIX," that measures anticipated shifts in the stock market.

With echoes of "Frankenstein" and HAL from "2001: A Space Odyssey," Harris's novel tells the story of Dr. Alexander Hoffman, an emotionally stunted but brilliant Geneva-based scientist and creator of a "super-computer" that uses complicated algorithms to operate an uber-lucrative hedge fund.

When Hoffman is attacked and then followed by a mysterious assailant, he suspects he's being impersonated. Soon, however, his prized VIXAL-4 system begins to act in unexplained ways, raising the chilling prospect that the creation itself could be the culprit.

"I had a kind of idea about a digitalized company that was so smart it really didn't need the employees anymore. That was the start of it," Harris said of the novel's genesis.

"The Fear Index" has received rave reviews, with financial types lauding its authenticity and others marvelling at Harris's ability to make the intricacies of a hedge fund understandable to the average reader.

The response is gratifying for the author, who spent time observing the industry for research purposes.

"Because I was a novelist ... maybe I got access that normally a journalist wouldn't get. A lot of what they do is highly confidential because they don't want their competitors to know what they do or how they do it, but I did get to see quite a lot of stuff," he said. "People talked to me in quite an unguarded way."