Joaquin Phoenix made his first return to The Late Show with David Letterman this week since his infamous February 2009 appearance, in which he appeared, as we now know, in character, as a maybe-drug-addled, bumbling shadow of his former Oscar-nominated self.

Phoenix's two-year spiral into what many assumed was a drug-induced breakdown (a still somewhat touchy parody, given his family's history) was all for the sake of I'm Still Here, a Casey Affleck-directed documentary exploring what Phoenix described as, "celebrity and the media and people who consume celebrity."

Ultimately, his for-film shenanigans included an attempted rap career, public paranoia, hosting prostitutes, using drugs and violently diving offstage to confront a heckling fan. (One of my favorite clips is of Phoenix desperately trying to convince Diddy of his legitimacy).

But of all the "is this really real" questions presented by the documentary, none is so interesting to me as the sexual harassment charges brought against Affleck during the filming. Two women on the production team, a producer named Amanda White and a cinematographer named Magdalena Gorka, sued the director for more than $2 million each. More significantly, the lawsuits were settled out of court — even though Affleck called them "completely fabricated."

So, was the drug use real? The recklessness? Did it lead a director to mistreat two members of his team? It's hard to tell where the documentary ends and reality begins, especially when Phoenix's erratic behavior seemed to persist when cameras weren't rolling.

It seems like a convenient vehicle for self indulgence. Maybe next year Lindsay Lohan will come out and say she's been filming a mockumentary, and she's so dedicated to her craft she couldn't break character. Would we buy it?

Watch the trailer for I'm Still Here below. What do you think? Was it art, or was it an act?