Joaquin Phoenix's journey from a serious actor to a hip-hop star is set to be captured on tape. Pal Casey Affleck will direct a documentary feature on Phoenix's new career.

When the Academy Award nominated actor announced last year that he is retiring from acting and will embark on a new profession as a musician, it was generally thought he would be a country music artist, just like his Johnny Cash role in "Walk the Line," or a rock music singer even. But very few expected him to enter the hip-hop world.

Now, Phoenix is on his way to become a rapper, with an album to be produced by hip-hop mogul Sean "Diddy" Combs.

His first public performance is scheduled on Friday at a Las Vegas club, which will kick off Affleck's shoot of the docu-film, as per Hollywood Reporter.