Joker: Every Death Ranked
4. Murray Franklin
The culmination of the movie sees Arthur appear on Murray Franklin's show. This should be his dream realised, not only for Murray to validate him (he imagines him as his ideal father figure) but also him becoming a "real" stand-up star.
In reality, his appearance on the show ends up being the final step in Arthur's Oedipal conflict. Murray's perceived rejection of him (when he mocks his comedy act) sparks the final fire in Arthur and stunningly, he shoots him dead live on TV. He got his moment.
Crucially, this is also the point where Arthur - who is going by Joker at this point - reclaims his own image. He's called a clown and a Joker, so he turns up dressed as one and billing himself as one. And he shows surprising awareness, considering he's shown to be such a delusional fantasist up to this point - he refuses to be exploited and manipulated and he bites back in a deeply disturbing way.