If you have not yet seen the documentary "I'm Still Here", that follows Joaquin Phoenix (aka JP) through his transition from famous and successful actor to wannabe rapper, then I highly recommend you do.
This documentary really has it all. From his unfortunate live performances and rapping to himself and his cohorts, to his mortifying interactions with Diddy (yes that Diddy) and a disturbing poop incident, you will run through a roller coaster of emotions. I personally felt confused, sickened, embarrassed for him, annoyed and amused.
Where does Joaquin go from here?
https://youtube.com/watch?v=wz6CU7pgiKc