You may wish 'I'm Still Here' wasn't here

An alleged documentary about Joaquin Phoenix's much-publicized decision to quit acting and pursue a rap career, "I'm Still Here" hints at but fails to answer the question most viewers will be asking: Is it real?

Directed by Phoenix's friend and brother-in-law, Casey Affleck, the film looks and feels real enough. Cameras jiggle and jerk and peer around corners as Phoenix behaves (acts?) like the self-obsessed, self-medicating train wreck we suspect Hollywood stars really are. The music he creates - a mix of loping beats and braggadocio date-stamped 1992 - is also just awful enough to be convincing.

There's also no doubting Phoenix's physical decline: Aside from the Dylanesque hair and Hasidic beard he sported for his now-notorious appearance on "Late Show With David Letterman," Phoenix looks 40 pounds heavier and three years short on sleep, and he yammers with the logic of the habitual drug user. It's easy to believe the cocaine he snorts (with two hookers) is genuine.

But something doesn't add up. Why is Phoenix's father played by Tim Affleck? Why is Phoenix credited as a co-writer? What is Sean "Diddy" Combs doing here?

If "I'm Still Here" is a joke, it's unclear who it's meant to amuse (besides its creators) or what it wants to say. The only way Phoenix could prove his sincerity would be to disappear from public view, but don't count on it: He's set to reappear on "Letterman" Wednesday and is reportedly in talks to return to acting.