Last week, shortly before the trial broke for a hiatus, Amber spoke on the stand about her marriage to the film star – and at one point referenced his ex-girlfriend, supermodel Kate Moss.
WATCH: Johnny Depp testifies in court against Amber Heard
Amber alleged that in a 2015 argument with her husband, she became concerned that he would harm her sister, Whitney, who was present at the time. She said that in that moment, she "instantly thought of Kate Moss and the stairs, and I swing at him".
Her comments sparked a big reaction from Johnny's lawyer, who could be seen celebrating and punching his fist in the air, as Johnny smiled at his side.
Johnny Depp's lawyer celebrates in court
It's not clear exactly why Johnny's legal team were so buoyed by Amber’s remarks – although it's sure to become clear when they are given the chance to cross-examine the actress next week.
It was initially thought that Kate's name was banned from being included in proceedings – but reports are now suggesting that Johnny's team might have evidence to disprove a rumoured incident between Johnny and Kate.
Amber Heard is set to be cross-examined next week
Kate – who is fiercely private – has never said that she was abused by Johnny during their relationship, which lasted from 1994 until 1997. It's not known if she will be called to take the stand to talk about their romance.
Three years after the couple's split, Johnny spoke about the end of their relationship – and admitted he was at fault. "I have never got that emotional over a woman before," he said in a candid interview with HELLO! magazine in 1998.
Kate Moss has never alleged abuse at the hands of Johnny Depp
"I have been so stupid because we had so much going for our relationship. I'm the one who has to take responsibility for what happened - I was difficult to get on with, I let my work get in the way and I didn't give her the attention I should have done.
"The whole thing was crazy because I should never have got so worked up over what people had to say about my work," he said. "Sure I should care about my movies, but when I get home I should try to leave that stuff behind. I couldn't do that and I was horrific to live with. Trust me, I'm a total moron at times."
The former 'it' couple dated from 1994 until 1997
Kate, who rarely speaks about her private life, later admitted to Vanity Fair that she had cried "for years" following the split.
"There's nobody that's ever really been able to take care of me. Johnny did for a bit. I believed what he said. Like if I said, 'What do I do?' he'd tell me," she shared.
"And that's what I missed when I left. I really lost that gauge of somebody I could trust. Nightmare. Years and years of crying. Oh, the tears!"
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