The curse of the Joker: The downside of playing the world's most infamous villain.

The ‘Clown Prince of Crime’ is back.

After weeks of controversy, rumoured security threats and Oscars buzz alike, Joaquin Phoenix’s take on the Joker is finally here.

The new film, simply titled Joker, joins a long line of portrayals of the world’s most infamous villain.

But while the comic book character has long been emulated in pop culture, there’s a popular theory that portraying the character comes with a dark side.

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

From Jack Nicholson to Heath Ledger, it’s long been believed that playing the villain has affected every actor who has played the role.

Here’s what we know about ‘The Curse of The Joker’:

Jack Nicholson

Although Jack Nicholson wasn't the first to play the Joker on the big screen, the actor's role in Tim Burton's 1989 film Batman is undoubtedly one of the most memorable portrayals of the villain.

Nicholson had already appeared in films like The Shining, but playing the Joker was a completely different ball game.

Speaking to MTV in 2007, Nicholson shared that the Joker was always a part he thought he should play.

"The Joker comes from my childhood. That's how I got involved with it in the first place," he said at the time.

The actor hasn't shared much about what playing the villain was like, but he famously quipped that he was "furious" when Australian actor Heath Ledger later landed the role in The Dark Knight.

When Ledger passed away from an accidental prescription drug overdose shortly after filming The Dark Knight, Nicholson told reporters: "Well, I warned him."

Heath Ledger

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

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

In preparation for the role, Ledger used method acting and even kept a chilling 'Joker journal' which included pictures of hyenas, clowns and comic strips. While working on the character, it's believed the actor sometimes only slept for just two hours a night.

"He pretty well locked himself up in a hotel room for week," Ledger's father Kim told German documentary Too Young To Die.

"He galvanised the upcoming character. That was typical of Heath. He would do that. He liked to dive into his characters, but this time he really took it up a notch," he added.

"At the end of shooting, he wrote goodbye on the back of the last page. It was hard to read that."

After finalising filming on The Dark Knight, Ledger shared that playing the Joker was one of the best roles he'd ever had.

"So far he's definitely been the most fun I've had with any character," Ledger said.

"He's just out of control, he's got no empathy, he's a sociopath, psychotic, mass-murdering clown."

On January 22, 2008, shortly after filming ended, Ledger was found dead in his hotel room following an accidental prescription drug overdose. He was just 28 years old.

In 2009, Ledger won a posthumous Oscar for Best Supporting Actor for his role as the Joker.

Jared Leto

The next actor to play the Joker was Jared Leto in 2016 film Suicide Squad.

Much like Heath Ledger, Leto also used method acting to dive into the Joker's mindset.

During filming, the actor and musician controversially sent his cast mates some unwelcome surprises, including reportedly mailing a live rat to Margot Robbie and delivering a dead pig to the rest of the cast. He also gifted Will Smith a set of bullets.

"There was a point where I was researching violence and I was watching a lot of things... things that it's arguable if anybody should even see. And I noticed that started to have an impact on me that I didn't like, so I stopped," Leto told GQ of his method acting process.

"It just starts to just get inside you, violence and some of those things. But you know, I've made some pretty dark films."

Leto was so committed to remaining in character while filming Suicide Squad that his co-star, Will Smith, never met Jared Leto on set – only the Joker.

Joaquin Phoenix

Joaquin Phoenix is the latest actor to portray the crazed villain.

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.

After landing the role, Phoenix admitted that deciding to pursue Joker terrified him.

"I take a lot of time and consideration when making decisions about what I'm going to work on," he told Collider.

"It feels unique, it is its own world in some ways, and maybe, mostly, it scares the f***ing sh*t out of me or something. It might as well be the thing that scares you the most."

In an interview with The New York Times, Joker director Todd Phillips shared that, at certain parts during filming, Phoenix would abruptly leave.

"In the middle of the scene, he'll just walk away and walk out. And the poor other actor thinks it's them and it was never them – it was always him, and he just wasn't feeling it," Phillips explained.

In preparation for the role, Phoenix created his rendition of the character's iconic laugh after watching videos of people who suffer from pathological laughter, which the Joker appears to suffer from in the film.

He also reportedly lost over 20 kilograms to play the gaunt character.

"As it turns out, [extreme weight loss] impacts your psychology, and you really start to go mad when you lose that much weight in that amount of time," he said, according to People. 

But while Phoenix went to great lengths to prepare for the role, he maintains that it hasn't affected him in a negative way psychologically.

"As humans, we're so malleable – it's probably how we survive and adjust and adapt," he said. "[When making a movie] my whole life changes. I go to a new city, I'm living in a new place. I don't have photos from home or anything that reminds me of my life," he said.

"I don't know if you know how it changes you, or whether it does. But I certainly don't have any great actor stories about having nightmares or [anything] like that. Honestly, I had so much fun making this."

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

For more on this topic:

• 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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