Joker Origin Movie: 9 Key Influences You'll See In Joaquin Phoenix's Performance

6. Case Study

Another comic book influence, Case Study - which features some stunning artwork from Alex Ross - finds the Joker back in Arkham Asylum, where an old report theorises that he isn't actually insane. Instead, it claims, he's a sane man committing crimes under the guise of madness as a means of getting revenge on Gotham.

While the storyline relates to the Red Hood, the bare bones of it could easily be retrofitted to suit a different Joker, and there are definitely hints of it at play with Phoenix's take. He starts the movie as Arthur Fleck, a man who isn't insane, and the idea of him committing 'sane' crimes fits with him going up against a Trump-esque Thomas Wayne. This is, after all, a Joker story without Batman, so it needs to flip the switch slightly, and that's a way of making it look like Wayne and co almost deserve Joker coming after them.

Case Study also documents Joker's fall into the chemical vat that would forever transform his appearance, which is something quite likely to figure into this movie: director Todd Phillips has been so open with sharing his appearance, you have to think there's a change coming - and a more permanent one at that - towards the end of the movie.