“Folie à Deux” is set two years later, after a TV movie about the Joker’s original killing spree, and Arthur is over the mass adoration of his hideously made-up Joker persona. Phoenix got his inspiration by imagining the real daily life of the ’70s rock band KISS.
“Did you ever think, how about Gene Simmons from KISS? Where 20-year-olds are painting their faces, putting on platform shoes, all rock ‘n’ roll,” Phoenix says, laughing. “But what happens when you’re in your 40s and like, ‘I don’t want to put the makeup on anymore’? I just started laughing about that. Todd and I were like, maybe that’s the beginning of something.”