Amber Heard witness appears to give away 'Aquaman 2' spoilers during Johnny Depp defamation trial

• A witness in Amber Heard and Johnny Depp's trial appeared to give away spoilers for "Aquaman 2."
• Entertainment industry consultant Kathryn Arnold spoke about Heard's role in the upcoming movie.

An expert witness for Amber Heard appeared to give away spoilers for "Aquaman and the Lost Kingdom" on Monday during her testimony in the ongoing defamation trial involving Heard and ex-husband Johnny Depp.

Depp is suing Heard over a Washington Post op-ed she wrote in 2018, describing herself as a victim of domestic abuse. Depp has accused Heard of ruining his career and reputation in the defamation case. Heard is countersuing Depp, claiming that Depp physically abused her on multiple occasions during their marriage and that her career was damaged after the actor's attorney Adam Waldman called Heard's allegations a "hoax."

On Monday, entertainment industry consultant Kathryn Arnold took to the stand to testify about the damage done to Heard's career, including her role in next year's "Aquaman 2," starring Jason Momoa. The actress said earlier in the trial that her part was "pared down."

According to Arnold, the first draft of the sequel gave Mera, Heard's character, a "strong romantic arc" and "some great action sequences." However, when Heard got later scripts, her role was "radically reduced."

Arnold said: "She ends up in the hospital early in this new 'Aquaman 2' movie and doesn't really come out until the end to kind of wrap things up. All the interactions with Momoa's character, and certainly the action scenes, were taken out."

Arnold didn't divulge exactly why Mera is in hospital in the new film but said it is because she is "injured" or "it had something to do with a baby." In the "Aquaman" comics, Aquaman and Mera do have a child together called Arthur Curry Jr., or Aquababy.

Arnold added that Heard trained "five hours a day for several months with a trainer" to do a big action sequence in the movie, only to learn her role had been reduced when she got to set.

Earlier this month, Heard testified that she "fought really hard" to stay in the movie.

Heard's talent agent Jessica Kovacevic also testified last week that Warner Bros. considered recasting the actress citing a "lack of chemistry" between her and costar Momoa. On Monday, Arnold also testified that Momoa and director James Wan were "adamant" that she stay for the sequel.

A Change.org petition to remove Heard from the "Aquaman" sequel has reached over 4.3 million signatures during the trial. However, producer Peter Safran told Deadline that "fan pressure" wouldn't affect a decision on whether to fire Heard.