From left, Amanda Fuller as Brittany Murphy in Lifetime's "The Brittany Murphy Story," and Brittany Murphy in Beverly Hills, Calif., Dec. 1, 2009.
camera (Lifetime | Gregg DeGuire/Getty Images) From left, Amanda Fuller as Brittany Murphy in Lifetime's "The Brittany Murphy Story," and Brittany Murphy in Beverly Hills, Calif., Dec. 1, 2009.

Amanda Fuller grew up watching Brittany Murphy so much that she and her friends would throw "Clueless" parties. Now, Fuller is stepping into the late actress's shoes for "The Brittany Murphy Story," set to air tonight on Lifetime at 8 p.m. EST.

"It's very surreal to be in this position," she told ABC News. "Beyond ['Clueless'] like 'Girl Interrupted,' and all the films she was a part of, I feel like molded me as an actor. Maybe there was a reason why it all came together this way."

"I knew her more from her blockbuster career, then came to realize [through her indie movies and other smaller roles] she's an incredible talent that was totally under utilized," Fuller said, comparing the late star to the likes of Marilyn Monroe.

Read: Was Brittany Murphy Poisoned to Death?

Related: Brittany Murphy's Final Movie to Be Released

Murphy had her big break in the 1995 classic hit featuring Alicia Silverstone, then forged a career all her own, starring in other movies like "Just Married" and "Sin City." She married Simon Monjack in 2007 and mysteriously died in 2009 at the age of 32 after going into cardiac arrest. She had been suffering from pneumonia at the time of her death.

Years later, Angelo Bertolotti, Murphy's father, claimed she was poisoned.

"I have a feeling that there was a definite murder situation here," he told "Good Morning America" last year.

Fuller, 30, is more inclined to agree that pneumonia and related anemia caused her death.

"I truly believe that what we know to be true from the coroner's report is what is true," she said. "I don't play into any of the controversy stuff, murder and all that."

The movie will show how Murphy changed quite a bit physically over her career -- losing weight and going blonde. Fuller said she can relate.

"I think most actors go through that," Fuller admitted, saying there have been people who focused on her weight and other physical attributes throughout her career.

Fuller noted Murphy's obsession with high heels "because she was so small."

"I think what was so ironic was people fell in love with her in the beginning as her authentic self," she added. "A crazy girl from Jersey with that quirky spirit and she never lost that spark."

Amanda Fuller as Brittany Murphy in a scene from "The Brittany Murphy Story," premiering Sept. 6 on Lifetime.(Courtesy Lifetime) Amanda Fuller as Brittany Murphy in a scene from "The Brittany Murphy Story," premiering Sept. 6 on Lifetime.

As for looking like Murphy, Fuller knows the two aren't twins.

"The movie is more about trying to capture her essence that she had and shed light to that struggle she had as she went further into the business," she said. "The producers told me 'This is not a look-alike piece.' Hopefully once people get into the story, they forget that I don't look exactly like Brittany, but follow the journey of the relationships."

Fuller said she learned a lot about Murphy she didn't know while filming the movie.

"I didn't know her mom battled cancer and both those times, Brittany basically dropped her career to be there for her mom," she said.

One person who does not agree with the story line of this movie is Murphy's father, Bertolotti.

“I am disgusted and outraged,” he told Examiner of the project. He said the story is "completely untrue."

Fuller said Bertolotti has gone as far as to tweet her. According to his tweets, Bertolotti claims he's upset that the biopic refers to his daughter as a "chunky monkey," among other gripes.

Sharon, Brittany's mother, has not been involved, but Fuller said, "I think if she were to see the film, she would see the intent was only to honor Brittany's memory and bring her beautiful spirit to life."

Fans of the late actress have also spoken out about the project on social media. But Fuller is unfazed and proud to be a part of the film.

"It comes with the territory," she said. "Everyone's going to have their opinions."

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