A mystery that has shaken the literary world for years -- the theft of hundreds of unpublished manuscripts from distinguished authors -- may finally be about to be solved.

In New York this week, the FBI arrested Filippo Bernardini, a 29-year-old Italian employee of major publisher Simon & Schuster.

He is accused of impersonating literary agents and publishers over email to steal unpublished works from writers and their representatives.

The alleged scam had been known in literary circles for around five years with Margaret Atwood, Ian McEwan and Sally Rooney among the novelists reportedly targeted.

Bernardini was arraigned in court in Manhattan on Thursday after being arrested by agents at JFK airport the day before.

He has been charged with committing wire fraud and identity theft between 2016 and 2021, crimes punishable by 22 years in prison.

"Filippo Bernardini allegedly impersonated publishing industry individuals in order to have authors, including a Pulitzer prize winner, send him prepublication manuscripts for his own benefit," said US prosecutor Damian Williams.

"This real-life storyline now reads as a cautionary tale, with the plot twist of Bernardini facing federal criminal charges for his misdeeds," he added in a statement.

Bernardini pleaded not guilty and was released under "home detention" with a $300,000 bond secured on his home, a spokesperson for the Southern District of New York told AFP.

Bernardini worked in London for Simon & Schuster, which said in a statement it was "shocked and horrified to learn of the allegations."

"The employee has been suspended pending further information on the case," the publisher said in a statement.

"The safekeeping of our authors' intellectual property is of primary importance to Simon & Schuster, and for all in the publishing industry, and we are grateful to the FBI for investigating these incidents and bringing charges against the alleged perpetrator," it added.

Unknown motive

Prosecutors say the suspect's modus operandi was well established. He would impersonate real people in the world of publishing by sending emails from fake accounts.

The addresses would be made to resemble the domain names of legitimate publishers but with a letter changed here and there. The indictment accuses him of registering more than 160 fraudulent domains.

What baffled alleged victims was that the thefts were never followed by demands for money, nor did the works ever seem to appear online or on the dark web.

In 2019, Atwood's agent revealed that the manuscript for "The Testaments" had been targeted.

Last year, New York Magazine reported that the Swedish editors of Stieg Larsson's "Millennium" series had been approached by a purported colleague in Italy who requested an advance copy so that it could be translated before release.

A New York Times investigation at the end of 2020 found that "Normal People" author Rooney, "Atonement" author McEwan, and actor Ethan Hawke had also been targeted.

Little is known about Bernardini. Screenshots from a LinkedIn profile that was inaccessible Friday described him as a "rights coordinator" at Simon & Schuster.

The biography said he obtained a bachelors in Chinese Language in Milan and a masters in publishing from UCL in London owing to his "obsession for the written word and languages."

One element of the story prosecutors hope to find out is what the accused's motivations might have been as the indictment does not mention whether he made any financial profit from the alleged thefts.