Being cast as an iconic character on the big screen is always a difficult undertaking, especially when the character has been played by other actors. There will be expectations from fans that need to be met, and the actors that rise to the occasion are often showered in praise and acclaim.

The Joker is as iconic as it gets from DC Comics, and he has been played by iconic actors like Jack Nicholson and Heath Ledger. In 2019, Joaquin Phoenix won an Oscar for his portrayal of the villain, and the preparation he went through was intense and caused some difficulties while filming was underway.

Let's take a closer look at how Phoenix's weight loss impacted things on the set of Joker.

Joaquin Phoenix Won An Oscar For 'Joker'

Back in 2019, Joker made its way into theaters with an exceptional amount of hype and a fair share of controversy. The iconic villain had been played by several notable performers on the big screen before, but it certainly seemed like Joaquin Phoenix was going to be doing something unique with the character.

Written and directed by Todd Phillips, Joker was a standalone film that solely focused on the villain's origins as opposed to focusing on Batman taking him down. This gave audiences something fresh to watch on the big screen, and they made sure to show up in droves at theaters worldwide.

In spite of the controversy surrounding the film, Joker managed to haul in north of $1 billion at the box office. As if that wasn't incredible enough, Joaquin Phoenix took home an Oscar for his performance in the film.

This was a huge moment for Phoenix, and it certainly made the intense preparation he went through for the film worth it.

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His Preparation Was Intense

Joaquin Phoenix had a tall order to live up to as the Joker, but he made sure to do things his way as opposed to doing something that another perform had already done.

"Maybe it's like doing a play, like you always hear about people doing something, 'You should have seen this actor in this performance,' but then other actors do it, and it's a different kind of film. I think that genre, comic books, kind of lends itself to having different people play the same character and interpret it in a different way," said Phoenix.

Much like other actors before him, Joaquin Phoenix underwent some intense preparation before filming got underway. The Joker is not an easy character to prepare for, and his preparation consisted of losing a considerable amount of weight.

"The first thing was the weight loss, that’s really what I started with. As it turns out, that impacts your psychology, and you really start to go mad when you lose that much weight in that amount of time. There’s also a book about political assassins that I thought was interesting, and breaks down the different types of personalities that do those sorts of things [I do in the film]," the actor said.

Once production was ready to roll, filming got underway. However, things were done quite differently during this shoot.

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The Weight Loss Complicated Things While Filming

So, how were things done differently while filming Joker?

According to Zazie Beetz, "The script was great. We rewrote the whole thing while we were shooting it. Literally, we would go into Todd’s trailer and write the scene for the night and then do it. During hair and makeup we’d memorize those lines and then do them and then we’d reshoot that three weeks later."

This is a different way of doing things, but there was a reason why it needed to be done.

"We had to do everything then because Joaquin had lost so much weight that we couldn’t do reshoots later on so we were figuring it out. But Todd’s quick at getting stuff done so we always had extra time," she continued.

That's right, Phoenix's weight loss was difficult to sustain, so reshoots were completely out of the question. This is practically unheard of, as most actors won't undergo this drastic of a transformation. As such, the cast and crew were forced to do things differently during production.

Related: Here's How Much Joaquin Phoenix Was Paid For These Movies

Despite the changes that needed to be made on the fly, the folks working on Joker did an amazing job, and the film wound up being a monumental success. It seems like a sequel to the hit film is happening, and matching the success of the original is going to be a massive undertaking by all involved.

Next: Before Playing The Joker, Joaquin Phoenix Passed On Playing Another DC Villain