Brittany Murphy’s widower, Simon Monjack, is making public accusations against Warner Bros. and plans to file a wrongful death suit, according to The Daily Beast. And Warner Bros. is firing back, calling the accusations “false, reprehensible, and defamatory.”

Monjack is blaming Murphy’s death on movie bosses, saying they fired the actress from Happy Feet 2 two weeks before she was found dead in her bathroom, from an apparent heart attack, last month. He claims she suffered the heart attack as a result of stress related to being let go from the project.

He also claims she was fired because of rumours that she was difficult on the set of the horror film, The Caller, from which she had recently been let go and replaced with Twilight star Rachelle Lefevre. The film was shooting in Puerto Rico and storied were that she and Monjack — who did Brittany’s hair and makeup — had been so hard to deal with (with Monjack sometimes showing up drunk) that producers had let her go. Other sources claim the studio was looking for a reason to fire Murphy and hire Lefevre.

“They killed her,” Monjack recently told TheDailyBeast.com. He said, “Warner Brothers relied on conjecture and hearsay about the Puerto Rico film for why they cancelled Brittany’s role in Happy Feet. You’re disposable as an actress or actor.”

And that, he alleges, is why she died. He said, “She was devastated. All she wanted to do was to make movies. She was waiting for the role that would revive her career, waiting for the call from Penny Marshall or Gary Fleder, people she had worked with before, that they might remember how talented an actress she was and call with a new magical role.”

A Warner Bros. representative is refuting the allegations, telling Access Hollywood that Murphy was never hired for Happy Feet 2 in the first place, and that studio bosses aren’t taking Monjack’s accusations lightly: “Any claim that Warner Bros. Pictures was somehow responsible for Brittany Murphy’s tragic death is demonstrably false, reprehensible, and defamatory. Despite press reports to the contrary, Warner Bros. Pictures and Ms. Murphy never entered into any deal for Happy Feet 2.”