Directer and co-writer Todd Phillips says the success of Joker was not related to Batman. Instead, he believes the appeal of the Clown Prince of Crime goes beyond the Dark Knight, which allowed for a standalone film.

Speaking with Deadline, Phillips was asked about the success of Joker and if it stemmed from the character's origin in the DC Universe. More specifically, if the popularity of the character was due to his dynamic with Batman.

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"I think it was more than that," Phillips said. "I mean, I think there are themes in the movie that really resonated with people."

Rather than a traditional origin story, Phillips and Scott Silver created their own version of the character that was morphed into a villain by the inequalities of society. In essence, Joker took the killer clown beyond the pages of Batman comics and presented him as an example of society's shortfalls.

According to Phillips, he and Silver had set out to write a movie that was "meaningful" to comic book fans but to also address ongoing issues in 2016 when the script was being written. This expanded into 2017, with Phillips stating they "really wanted to use Joker to make a movie about the loss of compassion and the lack of decorum in the world."

"I've been around the world with the movie," Phillips continued. "And, speaking to the audiences, some people see it as an indictment of America and other people see it as a mirror what's going on in their country, both with the lack of compassion and with the wealth and equality issues."

The social issues in the movie were arguably part of its appeal, with Phillips and Silver essentially using Joker as a platform to present these problems to mass audiences. While it made for an interesting movie, though, it understandably left some audience members uncomfortable. Joker was an unexpected avant-garde film that was meant to take viewers to a disturbing place, which left them to decide if Arthur Fleck was a villain or a victim.

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Despite having an R-rating, Joker has already grossed over $1 billion worldwide, with Phillips stating he was open for a possible sequel.

Directed by Todd Phillips, Joker stars Joaquin Phoenix, Robert De Niro, Zazie Beetz, Bill Camp, Frances Conroy, Brett Cullen, Glenn Fleshler, Douglas Hodge, Marc Maron, Josh Pais and Shea Whigham. The film is currently available on Digital HD on and will arrive on Blu-ray, 4K UHD and DVD Jan. 7.