LONDON - Struggling to write a story set in Celebration, the Disney-planned city in Florida, Robert Harris read about research that shed new light on the volcanic eruption that destroyed Pompeii.

"I wanted to write about a utopia within a superpower … trouble in paradise," says Harris. "I suddenly thought, 'Maybe I should transport my superpower back 2000 years and make it Pompeii rather than Florida or California."

"Pompeii" (Random House, $24.95), published this week, is a departure for the British journalist-turned-novelist whose previous books - including "Fatherland," imagining a world in which Germany won World War II, and "Enigma," about wartime code-breaking - were set in the 20th century.

But "Pompeii," Harris believes, has a peculiarly modern resonance. "Anyone who has ever been to Pompeii cannot be but haunted by it in the sense that this busy civilization was making money and having a very good time, and then, suddenly, bang. It's a very eloquent statement about the fragility of human life."

The novel is the story of a water engineer, Marcus Attilius, who is sent to beautiful and wealthy Pompeii in A.D. 79 to find out why the aqueduct isn't delivering water. The problem, it turns out, proves to be a warning sign of a far greater disaster that looms from Vesuvius, the volcano towering over the Bay of Naples that had not erupted in 1,500 years.

"We now know it's a lethal volcano, perhaps the most dangerous in the world. It will blow again, it's not a question of if but when," says Harris, who visited Pompeii and saw the remnant of the Aqua Augusta aqueduct. He decided to begin his story two days before the eruption.

"I would have a ticking clock because everyone of course would know the end of the book, that Vesuvius blows up. I did a classic countdown to disaster, so that the reader knows what's going to happen but the characters don't."

Close to the subject

Two years of research preceded the writing of the thriller, much of it enjoyable. "There were a lot of trips to Italy, a lot of pasta consumed, a lot of Chianti drunk in the interests of accuracy," says Harris. He also decided to include a real historical figure - the scholar-admiral Pliny the Elder, whose famous descriptions survived the eruption of Vesuvius, though Pliny himself was killed.

"It was a bit of a shock to my publishers when you tell them you're writing a thriller about Pliny the Elder - not even Pliny the Younger," he quips.

To his surprise, the "lava saga" has been his biggest hit yet in Britain, topping the best-seller list for a month.

Harris, 46, began writing fiction in the late 1980s. He works at home - an old vicarage in Berkshire, outside of London, where he lives with his wife, Gill Hornby (sister of novelist Nick Hornby), and their four children. Hornby is his only friend who is a writer; he finds the literary world "poisonous."

Instead, Harris says, he socializes with journalists and politicians, including Prime Minister Tony Blair, who invited him to lunch a decade ago when he was a rising politician and later allowed him unparalleled access during his first election campaign.

"We've kept up contact, with periods of coolness. We're in a warmer patch at the moment," says Harris.

While Harris has voiced criticism of Blair's Iraq policy, he stresses that despite parallels in his book between ancient Rome and modern America, he is not anti-American.

"It's a book really about any sophisticated, civilized society and the hidden dangers that lurk around the corner," he says. "It's whenever your fortune seems incredibly good that Nemesis comes around the corner to punish you."

Originally published on November 16, 2003