Near the end of the film, Arthur looks at a photo of his mom in her youth with the words "Love your smile -- TW" written on the back. This would seem to confirm the affair between Thomas and Penny but considering how unreliable the Joker is and his own flights of fancy, is he just imagining that?
Check out our theories about the ending of Joker below:
In a new interview with The Hollywood Reporter, Brett Cullen opened up about his interpretation of Thomas Wayne. "In the other films, he’s always portrayed as very kind and very successful and then he’s dead," Cullen laughed."This film delves into Thomas Wayne more, and we tackle the idea that if you’re a successful businessman then there are certain things you do to have that success, and sometimes those things are not pretty … sometimes they’re cutthroat. I think there’s a real edge to him, he’s very much based in reality."
Cullen said he was surprised when he read that twist in the script, and revealed that director Todd Phillips sees Thomas Wayne's secret as the key catalyst for Joker becoming Batman's greatest adversary.
"I went to Todd and asked, 'Are we playing this the way I think we’re playing this?'," Cullen recalled. "Todd responded with, 'What would be a compelling reason for the Joker to hate Batman so much?' The idea that the Joker is an illegitimate child that didn’t get anything from the Wayne family is a very compelling motivation for his character’s hatred."
Cullen added that "this movie makes you feel for Arthur, when you see him struggling with his mother. And she’s saying, 'Go see Thomas Wayne, he’ll help us. He’s a good man.' It’s gut-wrenching."It's interesting to note that child actor Dante Pereira-Olson, who plays Bruce Wayne in Joker, played the young version of Joaquin Phoenix's character in You Were Never Really Here. Did Todd Phillips know that and intentionally cast him as Bruce due to their resemblance? Maybe one day we'll get that answer but that would certainly lend added credence to the notion that Arthur and Bruce are half-brothers.
For more on Joker, check out our theories about how it could connect to Robert Pattinson's Batman reboot, our explainer on the ending, enjoy our rave review, find out why Joker doesn't have a post-credits scene, learn what director Todd Phillips and Joaquin Phoenix had to say about the controversy surrounding the film, get the story behind Joker’s makeup, find out which movies inspired Joker, and discover how Martin Scorsese helped out the DC film.
