Amber Heard may have once attacked her sister — and there’s video to prove it, Johnny Depp’s lawyers claimed Friday in a bombshell twist at his London libel trial.

Depp’s lawyer David Sherborne notified the court that his team had received footage Thursday night showing Heard’s sister Whitney Henriquez with bruises on her face and body shortly after the alleged assault.

“We were contacted to explain Amber Heard has a history of violence and attacking people,” Sherborne told the judge after asking that Henriquez, who is due back on the stand today, wait outside the courtroom during the disclosure.

“The material, we say, demonstrates Whitney Heard lied yesterday,” said Sherborne, who wants the surprise video admitted, according to the Evening Standard. “It goes to the issue of whether or not Ms. Heard was violent.”

Sherborne also asked the judge to bar the “Justice League” actress, who was in the gallery, from “using her phone” to communicate with her sister.

But the judge said he had no reason to believe Heard had not complied with the instruction not to talk to her sister about her testimony.

Henriquez testified Thursday that Heard had never attacked her and denied being “frightened or “wary” of her sister, according to the newspaper.

She said she once witnessed Depp grab Heard by the hair and repeatedly punch her in the head.

It’s unclear if the judge will let in the purported video.

Depp is suing The Sun newspaper for calling him a “wife-beater” in a 2018 article based on Heard’s allegations.

He has denied ever abusing his then-wife during their wildly tumultuous relationship, calling her “sociopathic.”

With Post wires