Joaquin Phoenix may be the new Ali G. Starring in the new Casey Affleck directed ‘documentary’ I’m Still Here, Phoenix, 36, plays a movie star named Joaquin Phoenix who’s decided to turn from film to rap. According to Affleck, however, the project is totally for real.

Most people who hear of the unlikely subject assume automatically that it’s a mockumentary, rather than a documentary. His 2008 announcement that he was leaving movies to become a rapper seemed to be sincere, yet few took the statement at face value. A memorable appearance on The Late Show with David Letterman in 2009, where the actor was glazed and incoherent led Letterman to end the segment with the pithy, "Joaquin, I’m sorry you couldn’t be here tonight."

But director Affleck insisted in a press conference after a showing at the Venice Film Festival that “there is no hoax,” adding, “It never entered my mind until other people commented on the movie." Phoenix himself did not attend, though Affleck assured the crowd that he was indeed in Venice.

The movie, which includes meetings with Ben Stiller and Sean Combs, is the result of Affleck’s taping Phoenix for a year and a half, and follows the actor around through both the mundane and the grotesque. Including nudity, drug use, violence and ongoing humiliation, the movie provides ample entertainment, whether it’s real or fake. –AMY LEE