Joker: 5 Theories That Actually Improve It
1. It Was All In His Head
There is the distinct possibility that Arthur Fleck imagined all of the events in the movie. This isn’t just the usual ‘maybe it was all a dream’ theory we see in films either. During the movie, we see Joker imagine that he is on the Murray Franklin (Robert De Niro) show, visualising himself being praised by Franklin.
Further, we see that Joker has also imagined or hallucinated his whole relationship with Zazie Beetz’ character. Consequently, we could draw from this that most of the movie could have been hallucinated by Fleck. His relationship with his mother may have also been a figment of his imagination, as well as the clown riot and his inspiration for their rampage.
The idea behind this theory is that the Joker made up the whole story while in Arkham Asylum, with the titular character even saying at the end of the movie “you won’t get it.” During the movie we have frequent cuts to the Joker incarcerated in Arkham, banging his head against a door. While we assume that this was in Arthur Fleck's past, perhaps it is his present. The whole movie is a delusion of the joker while locked away in Arkham.
The director of the movie, Todd Phillips, has also added fuel to this theory, claiming that “you could look at [the ending] and go ‘this is just one of his multiple-choice stories. None of it happened.’ I don’t want to say what it is.”