By Alasdair Sandford
BBC News, Paris
For someone who is not French, hardly ever speaks in public and is not even here, Jonathan Littell is creating a lot of fuss.
His photo is all over the papers. In Le Figaro he is shown, head cast back and cigarette in hand, blowing a plume of smoke up into the air.
Jonathan Littell's book has been both praised and panned
Any likeness to literary icon Jean-Paul Sartre probably ends there.
Even before he won the Prix Goncourt, France's top book prize, this author had already reached a mass audience far beyond traditional literary circles.
Such was the demand for his book Les Bienveillantes (The Kindly Ones) that publishers plundered paper reserves earmarked for Harry Potter to print an emergency run.
On the radio this morning listeners phoned in to talk about it, just as they did to complain about the latest train strike.
Jonathan Littell is not the first foreigner to take the Prix Goncourt. The fact he is American and lives in Barcelona is barely causing a stir.
The 39-year-old grew up in France, wrote his book in French and says he loves French literature.
Rather it is the nature of Les Bienveillantes that makes its success surprising to many - and to some, disturbing.
The book tells the story of Max Aue, a fictitious SS officer, who gives a first-person account of his part in the Holocaust.
The subject matter is hardly new. But what is enticing readers is the Nazi's cold, dispassionate account over more than 900 pages of how he went about murdering Jews.
"There were always reasons, good or bad, for what I did," he says.
Mr Littell, whose ancestors were Polish Jews, spent years researching the background to his book.
After university he worked for the humanitarian organisation Action Against Hunger. His job took him to places such as Afghanistan, Bosnia and Rwanda, providing him with plenty of material on the horrors of war.
Les Bienveillantes has received some gushing praise.
Jorge Semprun, a member of the Goncourt jury, said he was "stunned by this amazing book - it's the literary event of this half-century".
Well before the novel won its prestigious prize, the magazine Nouvel Observateur ran a story about it with the headline: "Look out, Masterpiece."
Others are mystified at the book's success.
"The story is terrifying, a journey through the hell of World War Two", said one Parisian bookstore manager.
Les Bienveillantes tells the story of an SS officer during the Holocaust
He has been selling at least 15 copies of Les Bienveillantes each day, and is amazed at its appeal.
"It is really hard, not for sensitive souls. There is no easy dialogue, you have to really want to get through it."
Some rivals of the book's publishers, Gallimard, believe many people abandon it well before the end.
One organised a debate, and said readers fell into three categories: those who gave up after 300 pages, those who thought it was a masterpiece, and those who felt ill at ease.
Another bookstore owner, Colette Kerber, said she found Littell's treatment of the subject matter shocking.
She told the newspaper Liberation: "It is cut-and-paste docu-fiction, written with his feet. To think they are comparing it to Grossman or Tolstoy!"
Jonathan Littell may not be too concerned by such criticism. The Goncourt award is likely to boost sales of Les Bienveillantes even further.
In addition, the author has had his request to obtain French nationality turned down twice. The word is, he may now be granted it.