Scarlett Johansson's 'Black Widow' paycheck is tied to box-office performance. She's suing Disney for releasing it simultaneously on streaming.

• "Black Widow" actor Scarlett Johansson is suing Disney over the movie's dual-release.
• The lawsuit argues that Disney violated her contract by debuting the film online and in theaters.
• A source said the move cost her up to $50 million since her salary is largely based on box-office performance.

Scarlett Johansson is suing Disney after the company simultaneously released her film "Black Widow" on its Disney+ streaming platform and in theaters, according to court documents shared with Insider.

The Wall Street Journal first reported the news.

Johansson argues that Disney violated her contract, potentially bilking her out of significant income, because her salary was largely based on box-office performance. A source told the paper the actor could be missing out on $50 million.

According to the report, Johansson was concerned about the movie being released in part on Disney+. Her representatives contacted Marvel to ensure that the movie would solely be released in theaters. The report also said Marvel's chief counsel said they would speak with her if those plans changed.

"Black Widow" raked in $158 million in its global box-office opening, while Disney saw $60 million in sales from at-home viewing purchases.

"It's no secret that Disney is releasing films like Black Widow directly onto Disney+ to increase subscribers and thereby boost the company's stock price - and that it's hiding behind Covid-19 as a pretext to do so," John Berlinksi, Johansson's attorney, told Insider in an email. "But ignoring the contracts of the artists responsible for the success of its films in furtherance of this short-sighted strategy violates their rights and we look forward to proving as much in court."

He also said this won't be the "last case where Hollywood talent stands up to Disney and makes it clear that, whatever the company may pretend, it has a legal obligation to honor its contracts."

A Walt Disney Company spokesperson told Insider that "there is no merit whatsoever to this filing. The lawsuit is especially sad and distressing in its callous disregard for the horrific and prolonged global effects of the COVID-19 pandemic. Disney has fully complied with Ms. Johansson's contract and furthermore, the release of Black Widow on Disney+ with Premier Access has significantly enhanced her ability to earn additional compensation on top of the $20M she has received to date."

Disney+ and other streaming services took the unprecedented step and debuted movies at the same time online and in theaters in 2020 because of the pandemic. For example, Disney's live-action Mulan remake saw a dual release, as did "Wonder Woman 1984" And "Zack Snyder's Justice League" on Warner Bros.' HBO Max.

Read more: Hollywood insiders say there's growing tension at Disney as CEO Bob Chapek chafes at Bob Iger's 'long goodbye'

But the move prompted backlash from the filmmaking world, including from directors Christopher Nolan and Patty Jenkins, who helmed the "Wonder Woman 1984" project. Many speculated how traditional filmmaking could be affected by releasing high-budget, high-quality movies online.

You can view the lawsuit in full below.