You may remember the much-watched clip of actor Joaquin Phoenix mystifying David Letterman. Or heard the news about his confusing plans to quit the movie biz and recreate himself as a rap star. His strange period of reinvention — the jury is out on whether the talented actor is having Kaufman-esque fun with identity or an enormously self-serious cuckoo — is documented in first-time director, and brother-in-law Casey Affleck’s I’m Still Here: The Lost Year of Joaquin Phoenix, which will hit theaters on Sept. 10. (The film has been in the news lately, with a fired crew member suing Affleck for sexual harassment and him hitting her back with a countersuit.) The trailer looks beautiful, and I’m a sucker for most behind-the-scenes looks at famous people. They always look so trapped by the mean lights of the paparazzi line, their hotel rooms so depressingly grand and anonymous. Phoenix’s bulging pot belly seems at once vulnerable and aggressive, an f- you to good health and Hollywood beauty standards. But why do I worry that the movie will lack any real sense of self-awareness or humor, and that its narrative structure will sag without a genuinely reflective subject holding it together?

What do you think? Is Joaquin Phoenix an artist or an attention-hungry buffoon? Could he be both? Did you check in or out during the water droplets metaphor? However silly you might find the akimbo nest that is now the man’s hair, do you still admire his very real gifts as an actor? (See evidence below: the “Folsom Prison Blues” number from Walk the Line.)