Rebecca Ferguson is dropping bombshell revelations about Hollywood's toxic culture—but she's keeping one explosive detail locked away forever.

The Dune superstar has broken her silence in a raw new interview, explaining why she'll never reveal the identity of the "absolute idiot" co-star who screamed at her so viciously that she had to film with a tennis ball instead.

"It wasn't about exposing them. It was about reclaiming my power," Ferguson confessed to Harper's Bazaar. "That moment was pure terror. I was frozen. Now? I'd grab them by the arm and say, 'We need to talk—now.'"

Rebecca Ferguson in 'Dune: Part Two'. Warner Bros. Pictures

Ferguson—who's gearing up for Dune 3 this December—admits Hollywood is slowly changing, but the scars remain. "People say we're too 'woke.' I say we're finally waking up," she declared. "The pendulum had to swing hard to find balance."

The nightmare unfolded on a major film set, where a top-billed actor erupted at her: "You call yourself an actor? This is what I have to work with?" Ferguson, left sobbing and abandoned by crew, made an unprecedented demand: remove the actor and let her perform opposite a tennis ball.

"Zero support. Zero safety net," she revealed on the Reign With Josh Smith podcast. "I was alone with a tennis ball and my dignity."

Internet detectives have obsessed over the mystery co-star's identity, but Ferguson has shut down rumors about Hugh Jackman and Tom Cruise—calling Cruise a "transformative" mentor who inspired her death-defying stunts, even while pregnant.

"Tom creates a playground of professionalism," she gushed. "Because of him, I rappelled down an opera house terrified of heights, and fought through morning sickness with a vomit bag on standby."

Yet, the unnamed "idiot" remains Hollywood's most tantalizing secret—and Ferguson vows it'll stay that way. "This is my story, not a witch hunt," she stated. "But let this be a warning: the era of on-set bullies is ending."