Frank Miller has only just finished his first film as a solo writer-director, but he is already one of the most important and influential figures in the movie industry. In the mid-1980s, Miller – along with a few others, most notably Britain's Alan Moore – redefined the less-than-glamorous superhero genre. He took over the monthly Daredevil comic in 1981, as both writer and artist, and turned it into the noirish, multi-layered saga of an obsessive vigilante. But it was in 1986 that Miller really made his mark, giving Batman a brutal, satirical makeover in a series of hugely popular graphic novels, The Dark Knight Returns.
If the title of this groundbreaking masterpiece seems familiar, it should do: Christopher Nolan's recent Batman films are deeply indebted to Miller, just as Tim Burton's were 20 years ago. In the intervening years, several other would-be blockbusters have been derived from characters either invented or reinvented by Miller, namely Daredevil, Elektra, 300 and Sin City, which Miller co-directed with Robert Rodriguez. But his influence on Hollywood reaches further than that. As one of the men who transformed caped crime-fighters from a camp joke into something much cooler and more resonant, he's partly responsible for the superhero films that pop up in cinemas every other week, from Iron Man to Hellboy (not forgetting, of course, The Dark Knight).
Yet, prior to Sin City in 2005, Miller had kept away from the movies for over a decade. His only brush with Hollywood had been drafting and redrafting screenplays for the forgettable RoboCop 2 (1990) and the forgotten RoboCop 3 (1993) – not a pleasant experience. "It was an experience I'm really grateful to have had," says Miller, in a Knightsbridge hotel suite, "but it taught me not to be a screenwriter. The comparison I use is that a screenplay is like a fire hydrant, and there's a line of dogs going all the way round the block. It made me realise that I didn't want to do it any more. Anyway, I was perfectly happy doing comics. And it wasn't until this crazy Texan showed up that I got involved in films again."
That crazy Texan was Rodriguez. Miller had resisted all previous overtures to film his Sin City comics, assuming that the ultra-violent, black-and-white adventures of his gun-toting psychos and Amazonian femmes fatale would lose too much in translation. But Rodriguez demonstrated how green-screen techniques could make the images on screen look exactly like their creator's drawings. Miller was converted. "To get my hands right into the most powerful storytelling form in the world is just a thrill beyond belief," he enthuses. "It's like being an explorer, like cresting a mountain and finding a whole other continent."
Miller, a weather-beaten 51, is now revelling in his new-found career behind the camera – so much so that he can be afford to be courteous about others' attempts to adapt his comics. "I'm the worst audience in the world for those," he shrugs. "If I've touched a character I can only see it my way, so when people ask me what I thought of Batman or something, I just say, 'Well, I didn't do it, so I hated it.'" He pauses, then chuckles. "But I did think they got the title right this time! [The Dark Knight]"
Charting Miller's association with the movies reveals an interesting illustration of the shifting balance of power between the two mediums of comics and film. In the 1980s, when he was already a living legend in the world of graphic novels, condescending directors would cheerfully pilfer his work while pretending they'd never read it. In more recent years, with Daredevil (2003) and Elektra (2005), Miller was acknowledged on screen, but the films suffered from his lack of input. Next up was Sin City in 2005, followed by 300 in 2006, an exceptionally faithful (though inferior) rendering of his graphic novel, which credited Miller as an executive producer. The movie business was at last getting the message: when it comes to adapting comics, if it ain't broke, don't fix it.
Finally, we arrive at Miller's new film, The Spirit. Starring Samuel L Jackson and Scarlett Johansson, it recreates a 1940s serial by another of comics' great innovators, the late Will Eisner. Miller, a friend of Eisner's for 25 years, was given free rein by the producers to write and direct something as heightened and playful as the source material, and the resulting labour of love is often identical to a comic strip. "Well, they didn't hire me because I came from cinema verité," grins Miller. It is a triumphant moment: where once comics were film's poor relation, distorted beyond recognition in the transition from small page to big screen, now it is film that goes cap in hand to comics, desperate for inspiration, even if it means ceding a measure of control to their writers that would have been unthinkable a decade ago.
"I like to use a metaphor here which is that it's as if there has been this dance going on between the two forms for decades, and now it's as though they have got engaged," says Miller. "A big part of that is the digital technology. But it's also the growth of more independent film-makers than there ever were – people willing to take the chance and really see the future."
Why has it taken so long for Hollywood to come around to Miller's way of thinking? "Hollywood is a bubble," he says, sounding like one of his own hard-boiled narrators. "It's cut off from the rest of the world. But every once in a while, when it gets really sick, it needs an infusion from somewhere else. Like in the 1940s, with film noir, it got that infusion from prose. I don't believe that something as quirky and wonderful as Hellboy would have come along from a studio system by itself. It's a healthy influx."
Miller could just as well be talking about the shot in the arm he gave comics 20 years ago. But he maintains that he didn't set out to turn the medium on its head when he moved from Vermont to New York to seek his fortune. It was a simple matter of sneaking his own preoccupations into a limited field. "I first showed up in New York with a stack of samples of my artwork," he says. "but none of it had superheroes. It was all guys in trench coats, and girls, and vintage cars – all the stuff that eventually became Sin City. But the only kinds of comics that were published were these guys in tights. But I had to do comics. It was the only ambition I had. So when the legendary artist Gene Colan left Daredevil I pushed to get the job myself, and what I did was I turned it into a crime comic – with one guy in tights."
Wasn't he aware he was revolutionising the genre? "No," he snorts, "I was mostly aware that I was pissing people off! People think of The Dark Knight reverently now, but when I was doing it, people around me were saying, 'You can't change Batman's costume! The fans were outraged – that's what I mostly heard. But sales were terrific, and I was able to make my living doing it. Otherwise I don't know what I would have done. Probably been a serial killer or something."
Star attraction: Why Frank Miller gets a kick out of Converse
Whether it's Daredevil's alter ego, Matt Murdock, or Sin City's Dwight, as played on screen by Clive Owen, or Denny Colt in the new film of The Spirit, Frank Miller's heroes are often seen running across city rooftops while sporting lovingly drawn Converse All Star boots. What's the big deal about Converse All Stars?
"Isn't it obvious? I mean, what's the big deal about the Pietà? They're beautiful!" responds Miller. "Also, it's always bothered me that superheroes wear dress shoes to run across rooftops, because if I wear dress shoes I can barely make it down a flight of stairs. But, yeah, we all have our trademarks, and Converse boots are one of mine, because they're fun to draw.
"There are certain things you learn as a cartoonist, and one of them is that nothing is really boring. If you actually look at it and figure out how it works, things are stranger than you think, and one of the most interesting things we wear is shoes.
"There's a reason women are obsessed with them. They're complex in their structure, because the foot is complex. Most people think of the foot as being the end of an 'L', whereas in fact the foot is as complicated as the hand and almost as dexterous. Now the headline's going to be 'Foot Fetishist Frank Miller'!"
'The Spirit' is out on general release