A serial killer reference and a Justin Theroux cameo: 9 details you might have missed in Joker.

Warning: This post contains spoiler for Joker. If you haven’t seen the movie yet, bookmark us and come back once you’re ready to properly debrief.

It’s been over a month since Joaquin Phoenix’s take on the Joker was released and it seems the hype around the comic book movie isn’t going away any time soon.

Although the new film, simply titled Joker, was shrouded with controversy and rumoured security threats amid its release, the film is now just days away from making a whopping $1 billion at the box office – making it the most profitable comic book movie in history.

Joker, which is the origin story of the Batman villain, follows Phoenix as Arthur Fleck – a failed comedian-turned-villain struggling to find his way in Gotham City.

Watch the trailer for Joker below. Post continues after video.

But while the movie joins a long list of portrayals of the ‘Clown Prince of Crime’, the standalone movie, which isn’t fully based on a specific comic, is packed to the brim with Easter eggs, references, and hidden details.

From similarities between Joker and Martin Scorsese films like Taxi Driver and The King of Comedy to a blink-and-you’ll-miss-it cameo from Justin Theroux, the movie manages to sneak in dozens of tiny details.

In case you were too busy recoiling over Phoenix’s disturbing Joker laugh, here are some of the tiny details you might have missed in Joker:

The story behind Pogo’s comedy club.

Throughout the movie, Arthur Fleck visits and later performs at a comedy club called Pogo's.

In a particular disturbing Easter egg, Pogo's is actually a reference to one of America's most notorious serial killers – John Wayne Gacy.

By day, Gacy performed as his alter ego, "Pogo the Clown." By night, he murdered at least 33 teenage boys and young men between 1972 and 1978 in Illinois.

The infamous subway shooting scene.

Arthur Fleck's breaking point in Joker takes place on a subway train, when Fleck fatally shoots three young men after they attack him.

The scene is tough to watch – but it actually loosely references an incident that took place in New York City in the early eighties.

On a subway train in 1984, Bernie Goetz drew a hand gun and shot four African American teenagers, who he claimed were preparing to rob him. Much like in Joker, the subway incident led to a huge firestorm of tabloid press and backlash in both New York City and across the United States.

"I was living in New York at the time so I remember it quite well," Joker costume designer Mark Bridges told Indie Wire, of the reference to Bernie Goetz.

"He was a very bland person, who had just had it, so there was a bit of that too: Art imitates life a little bit. If this already happened, it’s not a far stretch for someone who has been abused and misused enough to fight back, finally."

The nod to Martin Scorsese.

Joker is essentially a love letter to director Martin Scorsese.

In fact, the film has a lot of common with both Taxi Driver and The King of Comedy.

In the movie, late night talk show host Murray Franklin is played by Robert De Niro – the star of both Taxi Driver and The King of Comedy. The character of Franklin is also strikingly similar to Jerry Lewis – who De Niro plays opposite in The King of Comedy.

In terms of similarities to Taxi Driver, both Fleck and Taxi Driver protagonist Travis Bickle journal their disturbed thoughts in a diary.

Fleck also shared a gesture with his neighbour Sophie (played by Zazie Beetz), when she mimes putting a gun to her head, which directly mirrors a famous scene from Taxi Driver involving Bickle.

The actor who played Bruce Wayne is a familiar face.

The actor who played young Bruce Wayne, Dante Pereira-Olson, is actually a familiar face.

The young actor also played a young version of Joaquin Phoenix in Lynne Ramsay's 2017 film You Were Never Really Here.

The reference behind Fleck's dressing room.

Ahead of his appearance on Live with Murray Franklin, Fleck is given a dressing room numbered #404.

It's believed the dressing room references one of the most influential Batman comics – Batman: Year One (Batman #404).

The film takes place in 1981.

Although we're not explicitly told during the movie what year Joker is set, it's pretty easy to guess based on the movies referenced on movie theatre marquees throughout the film.

Films referenced include Blow Out, Zorro The Gay Blade, Wolfen, Arthur and Excalibur, which were all released in 1981.

In Warner Bros.' production notes for Joker, director Todd Phillips added that Joker channels the early eighties.

"We included a few elements from the canon and set it in a broken-down Gotham City around 1981 because that harkens back to that era and would remove it from the comic book world we're so familiar with in film today," he said.

The subtle Justin Theroux cameo.

Now that I’ve seen JOKER all I want is a spin-off movie where we follow Justin Theroux’s character (Ethan Chase) as he makes the film American Playboy.

— Drew Highlands (@drew_highlands) October 11, 2019

Justin Theroux has a blink-and-you'll-miss-it cameo in Joker. While preparing for his appearance on late night show Live with Murray Franklin, Fleck watches an episode of the show which Theroux appeared on as comedian Ethan Chase.

Atlanta and Spider-Man: Into the Spider-Verse actor Bryan Tyree Henry also has a short cameo on the film – when Fleck goes to the hospital to investigate his mother's past, he struggles with Henry over his mother's file.

Bryan Callen, who appeared in The Hangover, appears in Joker as a man working at the company that provides Fleck with his clown gigs, while director Todd Phillips is also heard voicing a comedian at Pogo's Comedy Club ahead of Fleck's disastrous stand-up set.

The talk show scene.

The talk show scene in Joker is largely based on a similar scene which took place in Frank Miller's comic Batman: The Dark Knight Returns.

In the comic book version of the talk show scene, however, Joker began his appearance by kissing one of the female hosts, while wearing a toxin on his lips.

At the end of the talk show appearance, almost the entire hundreds-strong audience of the show is dead.

The subtle nod to Heath Ledger's Joker.

In 2008, Australian actor Heath Ledger portrayed the Joker in Christopher Nolan's The Dark Knight.

Since its release, Ledger's career-defining performance has long been regarded as the best film portrayal of the villain.

In Joker, Phoenix emulated Ledger's Joker when he took blood from his mouth and used it to create a new red, sweeping smile – almost perfectly matching Ledger's infamous bloody scar in The Dark Knight.

Joker is available to watch in Australian cinemas now. It is rated MA 15+.

For more on this topic:

• The curse of the Joker: The downside of playing the world's most infamous villain.
• A cult, the death of a brother, and "incredible anxiety". The complicated life of Joaquin Phoenix.
• The subtle tribute to Heath Ledger in the new Joker movie trailer.
• The story about Heath Ledger that speaks volumes about his character.

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