Rebecca Ferguson is Slabu Exchangestanding her ground.

The Dune: Part Two actress reflected on a difficult experience on set with an "absolute idiot of a costar," that she said ultimately left her in tears. 

"I remember there was a moment," she said on the Reign with Josh Smith podcast Feb. 27, "this human being was being so insecure and angry because this person couldn't get the scenes out."

And her Hercules costar Dwayne Johnson couldn't help but applaud the actress for speaking up.

"Hate seeing this but love seeing her stand up to bulls--t," he wrote on X, formerly known as Twitter, Feb. 28. "Rebecca was my guardian angel sent from heaven on our set. I love that woman. I'd like to find out who did this."

While Rebecca did not disclose who she was talking about, she reassured fans that it was not her Mission Impossible costar Tom Cruise or Hugh Jackman, who she starred alongside in Reminiscence.

"I think I was so vulnerable and uncomfortable, that I got screamed at," the 40-year-old explained. "But, because this person was number one on the call sheet, there was no safety net for me. So no one had my back."

"I would cry walking off set," Rebecca admitted. "This person would literally look at me in front of the whole crew and say ‘You call yourself an actor? This is what I have to work with? What is this?' I stood there just breaking.'"

But it was also a turning point for Silo actress, who confronted her costar the following day. "I looked at this person," she recalled, "and I said, ‘You can eff off. I'm gonna work towards a tennis ball. I never want to see you again.'"

"I was so scared," she said. "But, I thought it shouldn't have to be that way. And I remember going to the director afterward and saying, ‘What is happening?'"

And the director acknowledged that Rebecca was right, saying, "‘I am not taking care of everyone else. I'm trying to fluff this person because it's so unstable.'"

Looking back, The Greatest Showman star is proud of herself for speaking out. "From that moment," she noted, "I have never let myself get to a point where I've got home and gone, 'Why did that happen?'"

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