Shortly after the Italian crime journalist Roberto Saviano arrived in New York last fall, he came into possession of an unusual map. Unlike your typical tourist map, this one had been specially made for him by Italian authorities, and marked places he was to avoid—many of them shops and restaurants run by Italian immigrants suspected of connections to the mob.

The forbidden locations proved irresistible. One afternoon, he donned what he calls his “hipster” disguise (glasses, hat, caterpillar mustache) and slipped into a restaurant indicated on the map, where he ordered and waited to see what would happen.

His food came. He ate it. No one noticed him at all.

Back home, Saviano can’t walk down the street without causing a stir. His 2006 exposé of the Neapolitan mob, Gomorrah, has sold more than 10 million copies in some 50 languages; a 2008 film version was nominated for a Golden Globe, and a TV spin-off series was the most-watched show in Italy last year. Saviano grew up in a mob-infested town near Naples (he saw his first dead body lying in the street when he was 13), and his indictment was personal and unrelenting. Gomorrah recounted the horrors of the Camorra (as the Neapolitan mob is known) in a way that demolished the reigning mafia myth: in place of cannoli and codes of honor, he offered child soldiers and bodies being dissolved in hydrochloric acid. In so doing, he forced many Italians to reckon anew with the gruesome reality of the mob.

Yet for all Gomorrah’s fury and fame, one of its most enduring legacies has been its effect on Saviano’s life. After some of the Camorristi featured in the book repeatedly and credibly threatened to have Saviano killed, he was assigned an armed police escort. He spent the next five years being shuttled around Italy between safe houses and police barracks, eternally holed up indoors. He’d become a member of “the community of the escorted”—his term for the collection of writers and journalists, including his now-friend Salman Rushdie, who have been forced to live under protection. By the spring of 2011, he’d had enough. He left for New York, hoping to regain some freedom; the city has since become the on-and-off base of his “exile,” as he puts it.

I met saviano at the West Village office of Penguin, his American publisher, one bitterly cold Friday in late February, his 3,060th day living under protection. He had emerged from hiding to meet with, of all people, his publicist. He wore a puffy blue coat and three shirts, and spoke longingly of his palm-tree-filled hometown. Balding, with an aquiline nose and a perpetually furrowed brow, Saviano could easily be mistaken for a subject of one of his books. He is known for his finger jewelry—one Italian newspaper has dubbed him the “Lord of the Rings”—and as he absentmindedly stroked his chin, his left index finger flashed a silver ring with an inscription in Hebrew: “When fear sneaks behind you, know it is a creation of your thoughts.”

Brooke Parsons, Saviano’s publicist, led us to a small, dark room, where a single chair sat in front of a white backdrop, surrounded by lights. A video camera was trained on the chair. While Matt Boyd, Penguin’s marketing director, fiddled with the camera, Saviano and I stood in the doorway, chatting in Italian. For a moment, our roles reversed, and he began interviewing me. Where was I from? How had I learned Italian? Was I a wasp? “No,” I said. “Irish Italian.” “Italian on your mother’s side?” “Yes.” Apparently satisfied, he smiled and sat down.

“Did Brooke tell you what we’re doing today?,” Boyd asked, before explaining that they were going to shoot a promotional video for the forthcoming English translation of ZeroZeroZero, Saviano’s first investigative book since Gomorrah. Saviano has spent much of his post-Gomorrah life as a talking head on Italian TV, and although he was winging it that day, he spoke dramatically, as if he’d prepared his lines well in advance. In ZeroZeroZero, he shifts his sights beyond the Neapolitan mob, to the global cocaine trade. His ambition, he explained to the camera, was to show readers that organized crime “is a part of your life—it’s close to you.” He’d written the book “for revenge” and “out of obsession,” he said, adding, “I really hope the public understands the blood price I paid for writing these things.”

After Gomorrah was published, Saviano’s parents were forced into hiding; nearly all his friends abandoned him. Lonely and consumed by regret for what he’d done to his life, he considered never writing again. But as the feeling wore off, he turned back to his old preoccupations. “Every hour seems pointless, wasted, if you don’t dedicate your energies to discovering, flushing out, telling,” he writes in the new book.

ZeroZeroZero is dizzying. It charts the bloody rise of the Colombian and Mexican cartels that control the global cocaine market, connecting them to a host of far-flung collaborators: Wall Street banks, the Calabrian mob, mariners in Greece, a son of a former president of Guinea. As in Gomorrah, Saviano spares no grisly detail—the book is rife with murdered police informants and severed limbs. But whereas he wrote Gomorrah in the belief that speaking out was in itself a powerful check on the Camorra, Saviano concludes ZeroZeroZero with a policy recommendation for how to undermine the cartels: “total legalization” of the drug. He knows the idea is a hard sell. “Finding cocaine in a pharmacy? Sure, it’s not the vision of a perfect society,” he told me. “But in time it will destroy the drug trade.”

When, in the course of reporting Gomorrah, Saviano wanted to make clear that the mob had its hands in the Italian fashion industry, he worked his way into a Camorra-connected sweatshop; when he wanted to show a mobster’s villa, he sneaked into one (and peed in the bathtub). In ZeroZeroZero, we get profiles of fascinating people—the Colombian supermodel Natalia Paris, who was the girlfriend of one of the DEA’s top cartel informants; the Wachovia whistle-blower Martin Woods. But many of the sketches lack the first-person vitality of Gomorrah. To some degree, this reflects Saviano’s changed circumstances: while reporting the new book, he visited about a dozen countries, but security concerns tended to keep him from venturing beyond local police stations.

Even in New York, where his celebrity isn’t strong, some people do recognize him. While apartment hunting last fall, he told me, he was waiting to see a one-bedroom when he noticed the building’s doorman staring at him. “I saw you on TV in Mexico!” the doorman said. (The Spanish translation of ZeroZeroZero had landed on Mexican best-seller lists.) “You’re the Italian writer!” Saviano denied it, but the doorman insisted, “It’s you!” He took his phone out for a selfie, which Saviano refused, and when the apartment owner arrived, the doorman explained who Saviano was. The owner looked nervous. Saviano pleaded in English—“No mafia problem! No mafia problem!”—while the doorman insisted, “This guy is a hero! A hero!” Saviano didn’t get the apartment.

Italian authorities, working with the NYPD and the FBI, have established strict rules for Saviano’s life in New York. He has a midnight curfew and a mandate to stay in the state unless he gets permission to leave. Every time he lands at JFK, he is detained—sometimes for hours—until the authorities clear his entry. His wallet reveals various fake identities. At one point in our conversation, he fished from his pocket an old ID from New York University (where he’d taught a course in 2011 on the organized-crime economy) and passed it to me, chuckling. A photo of a dour and very Mediterranean-looking Saviano sat incongruously above a name more fit for a British parliamentarian: David Dannon. When he returned to the U.S. last fall, he was issued a new ID—this one with a three-part Spanish name. “It’s better than Dannon,” he said.

When Saviano teaches classes in New York, he tries to stay under the radar (his NYU students were asked to not talk about their instructor’s presence), and he avoids making public appearances for fear of breaking the guidelines set by the police. His one public appearance in the city to date came in November 2011, during the Occupy Wall Street protests. He wanted to give a speech on the financial crisis at the movement’s base, in Lower Manhattan, and though authorities warned him not to, he went ahead, surrounded by a security detail. Shortly afterward, he said, he was forced to return to Italy for six months.

He told me that he realized he might have to leave America again at some point and find another place to lie low. He pulled out his passport and flipped through it from back to front, pages of expired visas blurring together. “Maybe Switzerland, maybe Canada, maybe France,” he said. “I always have a plan B in my head.”