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Johnny Depp

Johnny Depp narrowly avoided his ex-wife Amber Heard at Comic-Con on Saturday.

The 55-year-old stunned fans at the panel for Fantastic Beasts: Crimes of Grindelwald at the event in San Diego, when he showed up dressed as his villainous character, Gellert Grindelwald.

With his hair dyed platinum blonde, and wearing a black floor-length trenchcoat, Depp walked on stage to thunderous applause from the crowd, moments before the new trailer for the Fantastic Beasts sequel was screened.

"The great gift of your applause is not for me, but for yourselves," he said in character as the wizard. "Therefore, applaud yourselves."

While his surprise appearance went down well with fans, some noticed that the panel held just 20-minutes later was for superhero movie Aquaman, starring his ex-wife Amber Heard.

The pair were involved in a bitter divorce battle in 2016, with Heard accusing Depp of being physically and verbally abusive towards her throughout their brief union, and even obtained a temporary restraining order against the actor.

The couple struck a $7 million settlement, and the 32-year-old promised to donate the entire settlement in equal parts to Children's Hospital Los Angeles and the American Civil Liberties Union.

However, Heard appeared in good spirits as she discussed her new movie with her fellow Aquaman stars, including leading man Jason Momoa, Nicole Kidman and director James Wan.

Speaking about her time filming on the mainly water-based set, the actress, who plays Mera in the movie, joked: "My friends joke I'm wet in all my movies and I'm cold. I hate being cold. I had to be wet, so I would come to work, first in the morning, already cold. Get on a freezing cold sound stage. And they built a box... and I would just stand there holding my book away from the splash and just get hosed down. Every morning. Grown-a*s woman, here at work, getting hosed down."