I’m Still Here: a brave, bizarre experiment in filmmaking?

In 2008, Joaquin Phoenix made the surprising announcement that, with his reputation at its height following a Golden Globe-winning performance in Walk The Line, he was leaving the field of acting to pursue a career in rap music.

Over the next 18 months, celebrity magazines charted Phoenix's apparent descent into madness. He was putting on weight, cultivating an increasingly unruly beard, and footage of his abortive attempts at hip hop was repeatedly appearing on the Internet.

One clip in particular, which showed Phoenix falling off the edge of a stage after a particularly bizarre performance, scored hundreds of thousands of hits on YouTube.

Phoenix's breakdown appeared to reach its nadir when he appeared on the Late Show With David Letterman in January 2009. Dishevelled and monosyllabic, Phoenix mumbled quiet retorts while he chewed gum. When a noticeably perturbed Letterman asked, "So, what can you tell us about your days with the Unabomber?" the question was probably only half meant in jest.

Actor and filmmaker, Casey Affleck, charted Phoenix's doomed musical career in his film I'm Still Here, from the actor's early recordings in his homemade music studio, to his farcical last gig in a Vegas nightclub, in which he infamously screamed, "I got a million dollar bank account and you're makin' fun of me?" before launching into a furious fistfight with a member of the audience.

I'm Still Here is a warts and all, unflinching and sometimes shocking documentary. Except, of course, it's all entirely fabricated. The prostitutes, drug taking, violence, vomit and tantrums are all either scripted or improvised. While Phoenix, Affleck and his collaborators were all in on the act, those outside this close circle weren't, and that reportedly included even the actor's own Beverly Hills agent.

With I'm Still Here, Affleck and Phoenix appear to have invented a new form of gonzo filmmaking. For both actor and director, the film represented a huge risk to their reputations and careers. Making it meant that neither party could commit to much else for the best part of two years.

"I went broke," Affleck told the Telegraph last year. "I hadn't worked for more than a year, and I was pouring money into the movie. I had to stop for a month to do The Killer Inside Me. If I hadn't, I wouldn't have been able to finish the film. I was out of money. There was a lot at stake financially and, if we had left [the hoax] there, it would have been very damaging to Joaquin's career."

Viewed from every angle, I'm Still Here was a bizarre enterprise, its intentions further confused by the fact that Affleck admitted that the documentary was a "planned, staged and scripted work of fiction" mere days after its American cinematic release last September (and days before it opened in the UK).

There were those, however, that saw through the pair's fake celebrity breakdown from the very beginning. Fellow celebrities, including Gwyneth Paltrow, who worked with Phoenix on what was apparently his last film appearance, Two Lovers, said she "wasn't convinced" that the actor had retired at all. "There may be something going on - I don't know what," Paltrow said in an interview with ITN in March 2009. "I don't know what he's doing. Maybe it's just a big performance art piece or something."

"Performance art piece" was, as it turns out, exactly what I'm Still Here is, a sporadically fascinating, if misfiring experiment in postmodern movie making. There's evidence everywhere that Affleck's film hasn't quite gone to plan. Phoenix's aggressive rant at his audience in Las Vegas was, as the director later admitted, a calculated attempt to turn the crowd against him, but their reaction was stubbornly apathetic.

This feeling of awkwardness and indifference pervades much of their film. Suspicions that Phoenix's breakdown is a hoax are voiced almost from the beginning, and despite the repeated appearances of celebrity friends such as Edward James Olmos and Ben Stiller (all of whom were in on the act) to give the story validity, their presence actually has the opposite effect, and merely underlines the artificiality of everything we're seeing.

Nevertheless, there are moments in Affleck's film where his attempts at getting under the skin of celebrity culture actually work. Like the much-publicised breakdowns of Britney Spears, Robert Downey Jr or, most recently, Charlie Sheen, Phoenix's apparent meltdown is treated more with scorn than pity. Press photographers and celebrity journalists circle the actor, capturing or commenting on every pratfall with insatiable hunger, while his Hollywood peers gleefully mock his dishevelled appearance at awards ceremonies and on talk shows.

The film serves as an obvious, yet pertinent indictment of the public and media's obsession with fame, and how quickly adulation can mutate into something far more ugly and malevolent. In any other walk of life, it would be utterly unacceptable to poke fun at a person suffering from issues of mental health. For those unlucky enough to be a household name, it's open season.

I'm Still Here's exploration of creativity and the desire for adulation is more fascinating still. The film's fictionalised version of Joaquin Phoenix (who behaves uncannily like a young Jeff Lebowski) is a man constantly colliding with the limits of his talent. Hardly a natural musician, Phoenix nevertheless responds to his audience's heckles with bewilderment and irritation.

Having enjoyed years of awards and compliments as an actor, this alternate-world Phoenix fails to comprehend why the public refuse to take to his tuneless doggerel with the same rapturous applause. More than any other film of recent years, I'm Still Here shows just how painful the process of artistic creation can be, and how vulnerable it leaves the artist when their endeavours go hopelessly wrong.

I'm Still Here opens with a piece of (fake) archive footage that depicts a young Phoenix jumping from the top of a waterfall, and plunging into the jade waters below. In the foreground, his father looks on with pride. It's an incidental, yet quietly brilliant moment which, along with its final scene, crystallises the themes of Affleck's film better than its staged arguments ever could, of the childlike desperation for approval and validation from others that many artists crave.

Interestingly, I'm Still Here's critical and commercial reception was as tepid as Phoenix's brief career as a rap artist. Earning less than $500,000 according to IMDb, the film was a commercial flop, despite the considerable publicity that surrounded its release. An unfortunate example of life imitating art, Affleck and Phoenix's kamikaze essay on celebrity culture was treated not unlike the actor's final gig in Vegas, with a mixture of bemusement and apathy.

As a piece of cinema, I'm Still Here is both self-indulgent and depressing to watch. Phoenix's assumed character is also, at times, extraordinarily unpleasant, a self-obsessed, malfunctioning monster.

And yet, as repellent as the fictionalised Phoenix is, his performance is extraordinarily committed. Hollywood, and the Academy in particular, has long been obsessed with the idea of the transformation, of actors altering their appearance to assume a character.

Charlize Theron won an Oscar for her performance as dowdy killer Aileen Wuornos, while Robert De Niro won Best Actor for his portrayal of boxer, Jake LaMotta, in Raging Bull. Phoenix's turn as a spoiled, bloated actor, a kind of distorted self-portrait, almost feels like a parody of those Oscar-winning, transformative performances that Hollywood loves, and is almost as praiseworthy as Theron and De Niro's.

Affleck's film is a brave, one of a kind piece of work. Far from the money grabbing publicity stunt that many have suggested (a sentiment that probably explains the film's meagre box office takings), I'm Still Here is a flawed, yet sometimes fascinating experiment that shows moments of insight amid the extended scenes of shouting and squalor.

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