Taking a look at a final performance isn't easy. That was the case with Robin Williams during Night at the Museum. According to those behind the scenes, the actor struggled and wasn't himself both on and off set, realizing his performance started to drop because of his mental illness.

Brittany Murphy's last role came in Something Wicked. The film took years to finally unveil the final product. As we'll reveal in the following, it was an emotional experience for those editing the film behind the scenes. We'll take a closer look at her role in the film, and what her peers thought of her last performance.

We'll also take a closer look at Murphy's final days, and why her career was shifting at the time of her passing. Murphy wasn't landing blockbuster films at the time, and her late husband had a theory as to why that was taking place.

However, we'll start things off by taking a brief look at the cause of death, and how she could've survived had she went to the hospital sooner.

Brittany Murphy Was Suffering From Pneumonia At The Time Of Her Passing

Brittany Murphy
Instar

According to People, Brittany Murphy passed away due to a combination of both pneumonia and anemia. The prescription drugs Murphy was taking at the time made things worse, causing the intoxication.

People's source reveals, "She was really sick with pneumonia, very anemic, and she was taking medication," Coroner Asst. Chief Ed Winter told PEOPLE at the time, "and all that combined killed her."

There were no illegal drugs found at the time of her passing.

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It is believed by the same source that Murphy could have survived had she went to see a doctor sooner.

"This death could've been preventable," he said. "Murphy was planning on seeing a doctor, but she, unfortunately, passed away before she did. This was a case of a person with pneumonia who was anemic and was taking medication when she should've been getting medical treatment."

Murphy's husband had instead decided to keep her home, thinking she was battling a flu.

"I had no idea she had pneumonia. I took very good care of my wife, she was on an antibiotic, and she was taking cough medicine and doing all the right things," he said.

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The world lost a brilliant actress and that held true during her final performance, which took four years to edit.

Writers And Producer Joe Colleran Called Brittany Murphy's Final Performance, "Chilling"

Murphy's last project took place in 2014, appearing in the horror/thriller, Something Wicked. Writer and Producer Joe Colleran revealed with The Guardian that the film took years to edit, given that they wanted to display the best work possible from Murphy's final performance.

"It is an additional responsibility; you do want her performance to be the best it can be, because unfortunately it's her last performance."

"The first months of reviewing the footage and starting to put things together and then seeing her and hearing her voice, it's very emotional. It has been an extremely protracted process, but here we are."

As expected, looking back at the footage was an emotional process for everyone involved with the film. In the end, everyone was blown away by the late actress and how she performed in the film.

"Chilling," the producer says. "She just hit it out of the park. You can see why she was a celebrity and a star."

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At that point in Murphy's career, things seemed to be headed in a different direction as she wasn't appearing in big-budget blockbuster films like she was accustomed to years prior. But there might've been a reason behind her change in films.

Brittany Murphy's Career Was Headed In A Different Direction Prior To Her Passing

Brittany Murphy
Instar

Late husband Simon Monjack would also discuss his late wife's career. He did admit that things weren't going her way, and that was evidenced when she was dropped from a big budget film, Happy Feet 2.

Simon tells THR that Murphy was broken over the decision, and believes there was a conspiracy against her. Nonetheless, Murphy didn't see it that way, and just felt as though she wasn't able to show her true skills in a project.

“It wasn’t about the money,” he told me. “She wasn’t going, ‘Oh, I’m not being offered $10 million to do a movie.’ It was: ‘I’m not getting offered anything where I can really show what I can do. I can sing. I can dance. I can do all these things I was put on Earth to show the world,’ and somehow she was being blocked from doing it.”

Sadly, Murphy's husband Simon Monjack would also pass away just a couple of years after Murphy. He died of the same causes as his wife.