Casey Affleck's documentary about his brother-in-law, Joaquin Phoenix, turns out to be not the mockumentary it was expected to be. In a terse review on his website, Roger Ebert writes "A mind is a terrible thing to waste. The tragedy of Joaquin Phoenix's self-destruction has been made into "I'm Still Here," a sad and painful documentary that serves little useful purpose other than to pound another nail into the coffin." But on Entertainment Weekly 's website, Owen Gleiberman comments "The film's unflinching honesty is, in the end, its own justification. Affleck uses Phoenix's descent to forge a riveting -- and, in its way, cautionary -- case study of a celebrity self-destructively addicted to his own psychodrama."