But faking reality is no modern phenomenon. As far back as 1915, the film-maker Hilton DeWitt Girdwood was dressing British soldiers in German uniforms and getting them to surrender for the camera. Audiences have always had an appetite for tabloid sensationalism and if the right kind of reality isn't happening out there, there's always a documentary-maker ready to cast, choreograph and direct it.
If ratings-hungry reportage often slides from fact into fiction, then this year's Edinburgh Film Festival shows many dramas hijacking documentary techniques for added authenticity. Michael Winterbottom's Wonderland turns London into one big set. Video footage runs through the Australian cop thriller Redball. Even Atom Egoyan's stylised adaptation of William Trevor's novel Felicia's Journey includes home movies and artfully-contrived 1950s TV-cookery programmes.
Of course, playing about with bits of grainy video tape is not the same as making a full-blown "mocumentary", and it's here that film's tail- chasing fascination with documentary realism is most evident. Fake realism at Edinburgh this year runs from the no-budget horror The Blair Witch Project to Chi Girl, an intense psychodrama about a documentary-maker stalking a girl, stalking a man. Welcome to Hollywood charts the not-so- meteoric rise of faux film actor Nick Decker, while Scottish comedy The Big Tease sees a BBC camera crew led by Chris Langham following Glasgow hairdresser Crawford MacKenzie (Craig Ferguson) to the Platinum Scissors hairdressing championships in Los Angeles.
"When I got the script for The Big Tease there was an interviewer who asked the odd question," says director Kevin Allen. "My reaction was: `If we're going to use this device then we've got to really do something with it.'" Writers often use documentary style purely as an observational technique, but forget that the film-maker always has their own agenda. Langham's character, says Allen, "is a BBC guy, so you know exactly where he's coming from. He's got this character, Crawford MacKenzie, and he's an idiot. He knows he's onto something."
A former BBC documentary-maker himself, Allen enjoyed sending up reportage film-making "with an expensive camera and a big Hollywood set", but feels the fake documentary is starting to feel a little hackneyed. "Mocumentaries are quite dated now. We decided to frame our story as a documentary, but in terms of the look of the picture, we never pretended it was anything but a film. This was a comedy about a hairdresser, I wasn't exactly after gritty realism!"
Instead, he tried to make the movie look "as polished and filmic as possible. I mean, the camera's so shaky in The Blair Witch Project, there are audiences coming out with motion sickness."
For Allen, film-makers today are too concerned with realism. "I think you've got to create a sense of that through ensemble acting. If your characters aren't believable, then you might as well forget the whole film." Although he enjoyed using documentary techniques for The Big Tease, "it's not something I'd want to go near again in a hurry. Mocumentary's dull. It's been done to death".
"People rolled their eyes at Sundance when we said we'd made a fake documentary," says Tony Markes, a former actor turned film-maker who plays the unsuccessful star of Welcome to Hollywood, "but mocumentaries are a whole genre to themselves. Each one is different."
Unlike Allen, Markes and his co-director Adam Rifkin wanted to blur the boundaries between fact and fiction from the start. "We wanted to play with the idea of fame," says Markes, "to see if we could create a star simply through publicity. We couldn't lie to the media about what we were doing, so what I did was become Nick Decker for a year and a half. I changed my name, I've got three actor's cards saying `Nick Decker'." The role started to take on this strange life of it's own: "I was invited to pro-celebrity golf tournaments as Decker. I was signing autographs `Nick Decker'. I had an agent getting me work. Sometimes I would go out to two or three auditions a day that I couldn't even take the film crew to. I actually got a commercial as Decker." So was the off-screen Decker more successful than he is on-screen? "Oh no," laughs Markes, "that Nick Decker is a flat line. Nobody wants to know him."
Some bits of Welcome to Hollywood, says Markes, are pure documentary. "Often, we would take the camera into a situation where nobody knew what was going on, that way people would behave naturally. The fight Decker gets into at the Sundance party is a great example; if you look at the crowd, people are reacting as though it's real. It looks and felt real: I broke my thumb."
Markes attended Sundance, Cannes and even the Oscars as Nick Decker, being interviewed by the media and posing for the paparazzi with his screen girlfriend, Angie Everhart. When Markes's married co-star turned up at the Academy Awards with "Decker" on her arm, their picture made it into People magazine and Everhart received phone-calls from friends and family wondering who he was.
Fun stunts but, as far as Allen's concerned, when it comes to mocumentaries, it's not so much reality bites as reality sucks. "I'm not interested in realism, I'm interested in credibility," he says. "The only way you can capture reality on film is by sticking a security camera in the corner of a bank." As the creator of a candid camera TV show called In Your Face, Markes doesn't quite want to do that, but something close. "The only thing that could have made Welcome to Hollywood more natural would have been hidden cameras," he says, "and I'm going to try that next."
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