Joker is one of those films that, even though we saw it coming, still shook the movie world and the world at large by storm. This film from The Hangover director Todd Phillips was a crossover phenomenon. It was the anti-superhero movie about a character that is totally unredeemable. However, that didn't stop viewers from embracing Joaquin Phoenix's turn as Arthur Fleck, the man who would eventually become the Joker. So dense was this movie, so layered was it with themes and ideas about society, mental illness, and how we treat people that are different, that it often doesn't play like a film in the DC canon. And it's because of those those differences that we are able, in many respects, to get passed many of the heinous and despicable thing that the Joker does.

In fact, aside from being set in a place called Gotham City, and having characters with the last name Wayne, and places named Arkham, Joker plays like a character study that was actually from the 1980s. For this reason, there are many details that tip their hat towards DC's grandest comic franchise. It's almost as if they were left there to be found. Director Todd Phillips has often talked about how Joker is not part of any shared cinematic universe. In fact, there are articles out there that declare that Joker MUST not connect to any of the other Batman films. All of this is great, however, we've got 5 hidden details that show that, like it or not, Joker is very much in and of the DC world.

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Ethan Chase Is Everywhere

Justin Theroux (co-writer of Iron Man 2) appears briefly on screen on Arthur Fleck's TV as guest Ethan Chase on "Live! With Murray Franklin." It seems that this could be seen as an olive branch of sorts between dueling superhero movie mavens Marvel and DC, as Iron Man is very much one of the jewels in Marvel's crown. However, this isn't the first time that the name Ethan Chase has been used as a character in a Todd Phillips film. In Due Date, Ethan Chase served as the "real" name of Zach Galifianakis's character opposite Robert Downey, Jr. (which, if you think about it, sorta ties this whole thing back to Iron Man, right?) This is a neat little tie in that serves as a slight reminder of the depth and lore of both the DC and Marvel franchise. They are referencing movies and characters from within the past 15-20 years. Joker itself is a reference to movies from the 70s and 80s. With a history that goes this deep it seems that, should DC (or Marvel) be so inclined, they could literally make multiple films that were nothing but hidden details.

Does that Burning Limo Belong to Bruce Wayne?

In the moments after Arthur Fleck does away with Murray Franklin (Robert DeNiro) on his own show, we see a lot of images amidst the streets of Gotham City. One of these is that of a burning limo which seems to belong to Thomas Wayne and his family. This is only an assumption but he just happens to be the representation of oppression in the city of Gotham. He's the one who doesn't live among the people but rather behind tall gates that protect his mansion of a home. Thomas Wayne talks on TV about what everybody else needs to do to make their lives better. When he's confronted by Arthur Fleck how does he respond? Rather than have an ounce of compassion for somebody he's supposed to be a public/servant advocate for, he, instead, punches Fleck in the nose. So it seems fair that the burning limo we catch a glimpse of in the film, is most likely owned by Wayne and it's a solid set-up for his eventual demise. Of course, this is a legendary death that would go on to see his son, Bruce, become the legendary crime fighter that he is.

Arthur's Case Manager Debra Kane

In the film this character is Arthur Fleck's case manager/counselor at the U.S. Department of Health. She is trying to help Arthur through therapy. Arthur seems open to this but it's clear by their conversation that there's only so much Debra Kane (played by Sharon Washington) us going to be able to do for him. Their meetings are a small part of the film but they play into the story very specifically. In fact, this character is a tip of the hat to one who appeared in Andrew Vachss' "Batman: The Ultimate Evil". It also seems like the name Debra Kane is meant to remind people that this whole thing originated with Bob Kane (and Bill Finger) when Batman was brought to life in 1939 in Detective Comics #27. This whole "tip of the hat" to Batman's history and lore, is just one way that we see how, like or not, Joker is forever tied to this iconic superhero.

Zorro: The Gay Blade Was No Accident

When the "The Dark Night Returns" comic book came out in 1986, Frank Miller had the movie that the Wayne's see before Thomas and his wife meet their end as The Mark of Zorro. Given that there are similarities between Batman and Zorro (their desire to fight back against criminals, covering portions of their face, their all black attire, etc.), it shouldn't be a surprise that that film would provide a tip of the hat in both the comic books and the movies. Todd Phillips has kept all of this in line with Joker which is why Zorro: The Gay Blade, from 1981, is the movie that the Wayne's screen before the fateful events (created by Arthur Fleck) see them meet their doom. This is yet another detail that not only keeps Joker within the DC Universe, but also ties it further into the lore that came before it. Yes, it's fair to say that Joker is a highly unique "superhero" film. In many ways it is in a universe all its own. However, amidst the darkness that is the life of Arthur Fleck, Joker managers to shine a little light on the history from which it's long been a part of.

What's In the Name Of a Comedy Club?

When Arthur Fleck does his stand-up act that ultimately leads him to a head-on collision with Murray Franklin (Robert DeNiro), the act is performed at a club that has a bit of an odd name: Pogo's. When you do a little research you realize that this isn't some throw-away name. It's actually a reference to deceased serial killer John Wayne Gacy. Why might Director Todd Phillips have done this? Well, it just so happens that one of the things Gacy did, when he wasn't killing people, was perform as "Pogo the Clown" at various fund-raisers and children's parties. When you consider what Arthur Fleck becomes... what sort of statement is being made here? Is the comparison between Arthur Fleck and Gacy fair or even accurate. John Wayne Gacy left behind a heinous legacy of murder and brutality. In Joker, Fleck is obviously a brutal murderer as well... but... he's the Joker and this this IS a movie. Whatever you think about this film, that little reference is yet another example of just how layered Joker is amidst its many plays at popular culture and US History.