Todd Phillips’ Heath Ledger before him, Phoenix endured an intense transformation process to become DC’s Clown Prince of Crime — with numerous on-set incidents reported, leaving many people to ponder the effects of the role on Phoenix’s own mental health. In a break from the usual superhero fare, Joker tells the story of Arthur Fleck, a failed clown and a lousy stand-up comedian, who launches into a downwards spiral after years of mental and physical abuse, turning to crime and seemingly causing a social revolution within Gotham City.
For the majority of critics, Joker represented new possibilities within the superhero genre, telling a decidedly adult story about mental health and social decay, while others found it to be overwhelmingly mean-spirited. Regardless, it hit a nerve — and Phoenix’s portrayal is likely the central reason for the film’s success. How, pray tell, did he transform into such a complex and troubled character?
Speaking with the Joker's makeup, which he learned to apply himself (with makeup artists taking the reins during the actual shoot). During the pre-production period, Phoenix discovered that simple, all-white makeup was the scariest — lacking the pops of color that he sports for much of the film — and the look was utilized in a few choice scenes throughout the movie. Arthur’s clothing and cadence were inspired by footage that Phoenix watched from the 1960s, featuring a man being psychologically evaluated. While Arthur’s condition is kept fairly vague throughout the film, Phoenix identified post-traumatic stress disorder as one of the character’s central issues and, in researching the common side effects of the medication that Arthur might take, discovered via internet forums that weight fluctuations were the biggest problem.
While Phoenix intended to gain weight for the role, his collaborators disagreed and he instead lost 52lbs. “Once I’d lost that weight,” he said to Travers, “ I was aware of my body in a way that I hadn’t been.” This newfound physicality led to the now-famous stair sequence, where Arthur dances up and down a step street. Phoenix also mentioned his own physical hunger (resulting from the weight loss) affecting his portrayal, with Arthur in a near-constant state of longing.
Additionally, in an interview with Joker’s iconic laugh was a very stressful process for Phoenix, with the actor settling on “something that’s almost painful.” He viewed the laughter as a part of Arthur that was fighting to get out — creating a strained, convulsive effect that is both unsettling and pitiful in equal measure.
Returning to the effects of the role on Phoenix’s own mental health, it’s not something that the actor typically worries about (as stated on Popcorn with Peter Travers) and the stigma attached to the Joker role is likely a media invention — largely stemming from the untimely ing of the aforementioned Heath Ledger and his supposedly intense commitment to the role. That said, Phoenix was reportedly more volatile on-set, with director Todd Phillips telling Phoenix’s co-star, Robert De Niro said, “Joaquin was very intense in what he was doing, as it should be, as he should be”, though it's worth noting that De Niro was one of the few cast who didn’t experience one of the actor’s walk-outs first-hand during the production of Joker.
