There are Gone with the Wind enthusiasts who like to dress up as characters from the book. There are obsessive followers of James Joyce, Tolkien and Harry Potter, in book and film form. There are Trekkies, utterly immersed in the world of Star Trek, and Indiana Jones lookalikes, and Sherlockians fascinated by the works of Sir Arthur Conan Doyle.

But there is nothing in popular culture that can quite compare, for sheer breadth, expertise and passionate enthusiasm, with the fans of Bond, James Bond.

By the latest count, there are no fewer than 67 different websites devoted to 007. Bond has inspired imitators, parodists and a staggering array of merchandise, from dolls to underwear to deckchairs to cufflinks to chewing gum. There was even a communist version of Bond, named Avakum Zakhov, with a licence to kill in the name of Marxism-Leninism.

The Bond fan base is universal. The catchphrases from the films are familiar in every language. Say the words “James Bond” in any country of the world and the response is likely to be a broad smile. According to one estimate, more than half the global population has seen at least one Bond film.

As I have discovered from giving a number of talks on Ian Fleming and James Bond over the past few months, Bond fans tend to fall into distinct categories: enthusiasts for the books, fans of the films, and people who are equally keen on both. Each category tends to look down on the other two.

The level of expert knowledge among certain Bond fans can be quite alarming. On innumerable occasions I have been gently but firmly corrected by someone in the audience over some exquisitely obscure point of Bondology.

One reason why Bond inspires such fervour is his immortality: he can be shared down the generations and across the sexes; 007 never goes out of fashion, and never will, for every successive film evolves the character in step with the changing times. But the scale of the Bond phenomenon is finally a tribute to Fleming's skill as a novelist.

The fictional world he created around Bond is complete in itself, able to embrace the reader entirely and take them to an imaginary place that is at once exciting and familiar. As John Betjeman wrote to Fleming, only the Sherlock Holmes stories have achieved the same feat. “That is real art.”

Bond fans share a profound belief in the enduring fictional world that Fleming invented, but they do not agree on everything. If you do not believe me, try walking into a room full of Bond fans and saying loudly: “The best Bond was George Lazenby!”

— Ben Macintyre is the author of For Your Eyes Only: Ian Fleming and James Bond (Bloomsbury, £20)

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