Affleck kept the camera rolling as Walk The Line star Phoenix played himself in a series of bizarre situations as he pretended he was giving up acting to become a rapper.
Phoenix never came out of character for the duration of the mockumentary shoot and even appeared on David Letterman's The Late Show in America as his awkward alter-ego.
But despite the critical bashing he and Affleck took, the filmmaker is keen to have another go.
He tells Wenn, "I do want to do something again because I feel like that movie was an amazing experience for me. I love directing that way and working with Joaquin; I learned so much in a different position working with an actor but it also left a bad taste in my mouth a little bit."