There is a celebrated exchange in Tarantino's second movie, Pulp Fiction. In his trademark trick - a gangster delivering a poetic riff on some arcane aspect of popular culture - characters discuss the question of what a McDonald's Quarterpounder hamburger is called in France. The answer is "a Royale" because - as all Tarantiniboppers know - France follows the metric system. That speech, though, may soon be inaccurate. The way things are going, a Paris Quarterpounder will soon be officially re-named a "Tarantino".
How can this mania be explained? Perhaps, in homage to Pulp Fiction, which is divided into four stories, the paradox is best explored from different narrative angles.
The Cinematic Explanation? Is it possible that the hysteria witnessed in Britain this week is purely film criticism? That Tarantino is simply one of the greatest film-makers of the century?
The difficulty with this is that his body of work is extremely skinny. He has directed two films: Reservoir Dogs (1992) and Pulp Fiction (1994), of which the second is generally regarded as a less impressive variation on the first. He has also written the scripts for two other movies: Tony Scott's True Romance (1993) and Oliver Stone's Natural Born Killers (1994), although the second of these is disowned by Tarantino because of the director's departures from the written text.
There is a precedent for a young director generating such social fuss on so limited an output - and the hysteria about the early work subsequently being validated by posterity - but that was Orson Welles. Is it really possible to believe that Reservoir Dogs is another Citizen Kane? Factors other than cinematic ones must surely be involved in Tarantino-fever.
The Rock Star Factor? In general, the surest way for an artist to achieve an adulation and visibility beyond the limits of their chosen discipline is to be - in charisma and sexuality - a departure from the general standards of the profession. Youth, dishevelment and an air of danger will, if the artist is lucky, invite comparisons with rock stars. Martin Amis and Damien Hirst are obvious examples from the worlds of literature and art.
Yet Amis and Hirst were never actually mobbed by screaming teenage girls, as rock stars are. Tarantino has been, which should make him the ultimate rock star-artist, except that he has none of the other physical or personality attributes. Youth is part of his mystique - he was only 29 when he made Reservoir Dogs - but he is otherwise more like a Silicon Valley technobrat than a member of Blur. QT is not a cutie. His manner is that of a nerdy couch-potato. The response of the Tarantiniboppers is unlikelyto be solely hormonal.
The Brand Name Effect? Part of the reason that Tarantino has achieved such astonishing name recognition is clearly that his name is so unusual. Quentin Tarantino sounds half English aristocrat, half Italian-American. The syllabic rhythm and repeated sequence "n-t-i" in both first name and surname could have been the work of a graphic designer. Whether or not Quentin Tarantino becomes cinema's most famous name since Orson Welles, he has already benefited from having one of the oddest names since Orson Welles. How many other boys called Orson or Quentin have there ever been in America?
But, if Tarantino sounds like a brand name, vital to his appeal is that his films themselves have the stylistic recognisability of a logo. Woody Allen is probably the only other director whose work could be so easily attributed on the basis of an extractscreened blind to an audience, and, even then, viewers might be thrown by the director of Annie Hall in one of his Scandinavian moods. Tarantino's work, as director or screenwriter, is all cut - or, rather, chain-sawed, meat-cleavered - from the same cloth. Other writer-directors have used irrelevance-riff dialogue - Whit Stillman, David Lynch - and others have employed graphically stylised violence - the late Sam Peckinpah, Oliver Stone - but only Tarantino has put the two together. This gimmick, thisnovelty, is what has raised his profile so far so fast.
The instant familiarity of his house-style is shown by the prevalence of the Tarantino joke in popular culture. Much of the coverage of the addition of lesbian and rape scenes to the forthcoming BBC1 serial of Edith Wharton's The Buccaneers contained waggish references to what might happen if Tarantino ever adapted a classic text: the gang-rape and decapitation, say, of Mrs Rochester in Tarantino's Jane Eyre. Tarantino gags are everywhere from Steve Bell's If... cartoon strip in the Guardian to Garry Bushell's TV column in the Sun, where the critic assumed this week that his millions of readers would understand a joke about the violent Eric Cantona signing to appear in "the new Tarantino movie, Reservoir Frogs".
It is revealing in this respect that the reason for Tarantino's presence in Britain this week, and thus the scenes of hysteria that followed, was the publication and sale of printed screenplays of his work. Most other celebrated contemporary film directors have generally worked with adapted books or screenplays by others: this applies to Spielberg, Coppola, Scorsese, Kubrick, Stone. They all have strong visual signatures, but Tarantino is unusual in also having a trademark literary style, in speeches like the Quarterpounder one in Pulp Fiction.
Yet other writer-directors - Woody Allen, the Coen brothers - have possessed a vivid signature-style without achieving Tarantino's tenor of recognition. There must be something else.
The Outlaw Factor? Although it is the distinctive combination of comedy and violence that appeals to critics and cinephiles, it is almost certainly the violence that accounts for Tarantino's broader status as an icon. The sense of danger which is singularly lacking in the director's own persona is vastly present in his work. Though not associated with banned substances himself, his films are a banned substance: Reservoir Dogs is still denied a video release by British censors and there was much debate about whether Natural Born Killers should be allowed cinema exhibition here.
This outlaw status is the crucial part of the Tarantino mystique. What most troubles critics about the director's work - his lack of any moral perspective - is precisely what most appeals to his younger fans.
In academic circles, the first written source is known as the ur-text. A Tarantino original script, though, is always the urrrggggh-text. In person, Tarantino may resemble a cinematic equivalent of a trainspotter, but it is the blank-eyed violence of hismovies, their callous laughter at the dark, that has made him Hollywood's first rock-star director.