The mystery surrounding the group is deepened by their refusal to be photographed. “Dear James, we can’t have a photographer running around during the interview,” reads an e-mail from Roberto Bui, otherwise known as Wu Ming 1. “No photographers and no faces — those are our conditions.” His promise to take me somewhere “in the hills” after our chat sounds faintly threatening. I wonder whether they might be considering kidnapping a journalist.

As it turns out, there is no need to worry. The only connection between the Roman hijackers and this Bologna-based writers’ collective happened to be their choice of pseudonym. They can’t explain the Luther Blissett tag, other than that it was a name used widely by artists and hackers in mid-Nineties, mostly for planting fake stories in the media. Besides, their involvement with the Blissett persona is history. The four original members — Bui, Giovanni Cattabriga, Luca Di Meo and Federico Guglielmi — discarded him at the end of 1999. Since then they have added a fifth member, Riccardo Pedrini, and assumed the name Wu Ming, which means “Anonymous” in Mandarin.

Only two of the group, Bui and Guglielmi, turn up to talk. We’re meeting to discuss their latest novel, 54, which was published in Italy in 2002 and has just been translated into English. Like Q, it is a sprawling epic, although the setting is modern. With the exception of a brief prologue, the action takes place entirely in 1954.

The plot is a formidable feat of imagination that moves restlessly between Bologna, Naples, California, Moscow, Dubrovnik and Marseilles. One story traces a young Italian’s quest to find his father, a former partisan who deserted Mussolini’s army to fight alongside the communists and disappeared in Yugoslavia. A second follows a Neapolitan mafioso as he plots to steal the profits of a drugs deal. The most daring, though, imagines Cary Grant in retreat in Palm Springs, sick of the movies and considering retirement, but being persuaded to undertake a secret mission to Yugoslavia to talk to Marshal Tito about making a film of his life — all with the aim of buttering up the dictator and drawing him away from the Soviet Union.

Grant is not the only historical figure to appear. David Niven, Alfred Hitchcock, Grace Kelly, Tito and the head of the KGB, General Serov, all make cameos. Occasional newspaper clippings give snapshots of the world that year: the defeat of the French forces at Dien Bien Phu, the death-throes of McCarthyism, sabre-rattling by the US as it tries to protect its economic interests in South America, and civil unrest in Trieste, still occupied by the Allies nine years after the end of the war.

Drawing them all together is an expensive American television set, stolen from an army base near Naples, which passes from one fence to another, occasionally turning narrator to berate the Italians for their barbarity and lack of respect for such a fine piece of technology.

The panoramic vision of the new book and its predecessor, according to Bui, is a reflection of the way it was written — the work of five brains. Guglielmi says: “This kind of literature that has a wide scope, that uses lots of characters and moves around a lot in the world is not a very individualist literature. It’s choral.”

Bui says: “And a choral novel isn’t going to be what you’d call a novel of family life with an intimate setting. That is another kind of novel, that has its own fans, but we’re not among them. We prefer to show the whole of the complexity of life, with all its possibilities, all its characters. We’re maximalists, not minimalists.”

There has been collaborative fiction before. A few years ago a group of Irish writers, including Roddy Doyle and Colm Tóibín, jointly wrote Finbar’s Hotel, a novel in the form of seven loosely connected stories. Chapters were left unsigned. The novel 54, however, is collaborative fiction in a more radical sense. “On a practical level it’s not much different from normal writing and editing, except maybe the fact you do the two things simultaneously,” Guglielmi says. “From a plot point of view, each person has a task — we all write a chapter or a scene and then show it to the others, who intervene, suggest changes and modify it and so on. At the end what you have is a book written by everyone, that has already been edited. It’s clean. Each of us is both novelist and editor. It’s as though the two professions were one.”

The writers meet every three days to check that five different writing styles aren’t pulling the fabric of the book apart. The process can be slow. “We take years to write a novel,” Bui says. “Q took three years, 54 two and a half.” It’s a method that also leaves plenty of scope for “artistic differences”.

For Bui the attraction of writing with other people is simple: “It’s fun. We’re a band — not a band of musicians, but a band of storytellers,” he says. He views collaborative process as part of an ancient, oral storytelling tradition. It’s a tradition that survives in large-scale projects such as Hollywood screenwriting, but is rare among novelists. “The writer is a storyteller, like the medieval minstrels, like the bards in Celtic culture — a figure that tells tales and is in touch with the people,” he says. “He’s not a person that lives in an ivory tower, isolated and somehow in touch with finer feelings — all that stuff is part of the Romantic myth of the author.”

What about their refusal to be photographed? It must make life difficult for a group of writers whose first book sold more than a quarter of a million copies worldwide. Anonymity isn’t the point, Bui says. After all, their names are posted on Wu Ming’s website. It’s a form of protest against our celebrity-obsessed age, he says: “The whole machinery of the writer as a star, or as a celebrity, does not interest us. We don’t allow ourselves to be photographed because we believe our work is more important than our faces.”

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