Since his breakthrough in 1991 with his documentary of Francis Ford Coppola at work, Hearts of Darkness: A Filmmaker's Apocalypse, director George Hickenlooper has split his time between independent documentaries and features, including Billy Bob Thornton's Some Folks Call It A Sling Blade (1994) and The Man from Elysian Fields (2001). In his latest film, Mayor of the Sunset Strip, Hickenlooper profiles legendary Los Angeles radio DJ and 'scenester' Rodney Bingenheimer, who introduced America to David Bowie, the Sex Pistols and Oasis but is now viewed as a relic of a bygone era.

Why make a film about Rodney Bingenheimer?

I knew who Rodney was - I had lived in LA for some years at that point - he has amazing taste and he used to play really great music. I was really interested to meet him, but I was dubious as to whether or not his story would make a very compelling feature-length documentary. So I met Rodney and we went to his apartment and it was covered floor-to-ceiling with photographs with this array of characters and celebrities from the music and film worlds. And when Rodney would talk about these pictures, he would become very luminous - he was abandoned at the age of 15, and there was so much pain in his childhood that he got rid of it and filled it with celebrity and music.

I saw [Rodney] as a very universal story and, without wishing to sound pretentious, I saw him as a kind of metaphor for where American culture has come in the last 30 years; how we've become very fragmented and how a lot of those gaps are filled with celebrity.

The film is a treasure trove of rock and roll images and classic music. What was it like putting the film together?

90% came from Rodney. Rodney is the most well documented individual I've ever met! Rodney had all these great clips on really bad VHS tapes so the real challenge was finding the masters. The whole process took five or six years. As for the music, David Bowie - who loves Rodney - gave us two of his songs for virtually free, which created a sort of favoured-nations deal, which allowed us to get all this music. We've got a Led Zepellin song and they've only licensed to three other movies before.

Were you ever concerned that the project rests on a double standard - that the film condemns and pokes fun at fame whilst using its allure to attract an audience?

Absolutely. I don't know how to answer the question other than to say that Rodney's story, by itself, is the story of many young American kids who come from broken homes. Outside of the world of celebrity, no, it's probably not that interesting. But what's interesting about it is that the celebrity around Rodney is an extension of his need to be loved. And the overall theme of the film is that celebrity is an extension of the human need to be loved.

Away from the limelight, Bingenheimer is a very sad character. You have to ask some difficult questions as an interviewer, notably of Rodney's parents. Is it very hard to twist the knife?

We were invited to Rodney's parents' house and the first thing my cinematographer noticed was that there were no pictures of Rodney anywhere, so I wanted to ask them about the photographs. I felt like it was a hard question, but I felt like it needed to be asked. That moment, where they can't find a photograph of Rodney, really sums up who Rodney is. Without pigeon-holing or sounding condescending to his life, that was the moment I thought 'this is what my movie's about'. I knew I had a really good film when that happened.

Was there ever a time when you were starstruck during the making of the film?

Only once. I wasn't that starstruck with Bowie for some reason. I've made so many films now, worked with so many stars, that it doesn't have an effect on me. The only person I was really starstruck with was Paul McCartney, who appears for a nano-second in the film. I met him twice with Rodney. He really likes Rodney. I had a camera with me but Paul's about as well protected as the President.

The last couple of years have seen a surge of documentaries in cinemas - films like Etre Et Avoir, Touching The Void and Spellbound. Why do you think they're so popular right now?

I just think audiences haven't been able to connect on an honest, emotional level. They've been deluged with special effects or post-modern, Tarantinoesque quirky movies that don't work on that level and I think documentaries have filled the gap.

Rodney's life seems pretty awful in the film, what's happened to him since it was made?

I think he's in good spirits, he seems very happy. Since the movie premiered at the LA Film Festival he's got women interested in him now - for all the wrong reasons!

Mayor Of The Sunset Strip is released in UK cinemas on 11th February.