Casey Affleck has finally come out and admitted that his "documentary" on Joaquin Phoenix, I'm Still Here, is indeed fake.

After a strange appearance on Letterman last year, when Phoenix was incoherent, rambling and generally hilarious, it was revealed that brother-in-law Affleck was filming a documentary on Phoenix's attempts to become a rapper. Affleck told The New York Times "It’s a terrific performance, it’s the performance of his career," after confirming that "virtually none" of the film was, technically, an actual documentary. "I never intended to trick anybody. The idea of a quote, hoax, unquote, never entered my mind."

The film opens exclusively at The IFI on October 1st.