Phoenix sinks to low lows. It's still hard to sympathize with him. The key moment of "I'm Still Here" comes when he appears on David Letterman's "Late Show," the much-talked about appearance that featured Letterman making fun of Phoenix's inability to utter coherent sentences. Phoenix had a third grade-level retaliation: sticking gum on Letterman's desk. Cameras show the nerves that led up to Phoenix's appearance and the breakdown that follows -- he demands that his driver stop the car so he can go cry in the bushes of Central Park, whimpering about how everyone thinks he's a joke.
But even if Phoenix is a totally baseless individual, even if the film is not 100-percent documentary, there's something redeemable about "I'm Still Here." It paints the picture of the fame monster that drags down people who have (or had) talent but no grounding in reality -- a beast that some might argue dominates the better part of Hollywood. The "is this guy for real?!" factor makes the movie riveting. Phoenix's unpredictable tantrums make him as watchable as he is loathsome.
The story of "I'm Still Here" isn't over yet. Phoenix is scheduled to appear on Letterman's "Late Show" on Sept. 22, presumably to promote the movie that no one can quite figure out how to categorize.