Johnny Depp and Heard met during the making of "The Rum Diary" in 2011 and married four years later.
Johnny Depp's opening statement is expected on Tuesday against his ex-wife Amber Heard in the US defamation case, the latest chapter in a long-running legal battle between the two Hollywood stars.
Depp, 58, is suing Heard for $50 million, alleging he defames her when she wrote a 2018 opinion piece about domestic abuse survivors in the Washington Post.
The op-ed never mentioned Depp by name, but Depp's lawyers have said it was clear that Heard, 35, was referring to him, and that his film career and reputation were damaged.
Known for his work in the "Pirates of the Caribbean" franchise, Depp has denied all allegations of abuse. Depp said in his lawsuit that Heard's claims were "an elaborate hoax to generate positive publicity for Ms. Heard and advance her career."
A state court judge in Fairfax County, Virginia is overseeing the trial, which could last up to six weeks. A jury was selected on Monday and opening statements are due to begin on Tuesday.
The US lawsuit comes less than two years after Depp lost a defamation case against The Sun, a British tabloid that dubbed her a "wife beater."
In the US case, both Depp and Heard presented long lists of potential witnesses they could put on the stand.
Heard's list includes her ex-boyfriend and Tesla chief executive Elon Musk, whom she wrote about Depp. Actor James Franco is also on the list of possible witnesses.
Depp wants jurors to find out that Heard intentionally made false claims.
Hurd, for her part, will argue that she told the truth and is shielded, or "immune," from liability because her 2018 op-ed on domestic violence is of public concern.
"I never took her name. Rather, I wrote about the price women pay for speaking out against men in power. I continue to pay the price, but hopefully when this case ends, So I can go ahead and so can Johnny," Heard said in a statement released Saturday.
The Washington Post is not a defendant in the lawsuit. Depp's lawyers have said he filed the case in Fairfax County, outside the District of Columbia, because the newspaper appeared in a facility there. Heard unsuccessfully tried to move the case to Los Angeles, where he and Depp lived.
The United States is a difficult platform for libel plaintiffs, especially public figures like Depp, who face many obstacles in the Virginia case. Depp must prove with clear and solid evidence that Heard knowingly made false claims.
Depp and Heard met in 2011 while making 'The Rum Diaries' and married four years later. Heard accused Depp of domestic abuse after filing for divorce in 2016. (Reuters)