LOS ANGELES − Dave Bautista was literally in beast mode for 2021's "Dune," terrorizing on screen as the sadistic Rabban "The Beast" Harkonnen.

Still, the former WWE star fretted for seemingly forever awaiting word on who would play his even more menacing younger brother Feyd-Rautha Harkonnen in "Dune: Part Two."

"I had this anticipation," says Bautista, who just wanted to know. "The rumor I kept hearing was that it was going to be Tom Hardy."

But months before Austin Butler's star-making turn as Elvis Presley in 2022's "Elvis" was unleashed on smitten audiences, the young actor was cast in the sinister role for director Denis Villeneuve's second "Dune" film (in theaters Friday).

"When I heard it was you, I was excited," a beaming Bautista, 55, tells his co-star Butler, 32, during a joint Harkonnen brothers interview at the Four Seasons Hotel. "And I was more excited when I met him. I mean, just look at him, he's just so lovable."

All very true. Except for some big "Dune: Part Two" red flags, starting with the "lovable" part.

The unrecognizable Butler is positively frightening as the bald, eyebrow-less warrior Feyd-Rautha in "Dune: Part Two" − the dark rising power in the dreaded Family Harkonnen that rules the warring planet of Giedi Prime from Frank Herbert's "Dune" sci-fi novels.

The heartthrob star's reveal as the eye-popping archrival to Timothée Chalamet's Paul Atreides has been the biggest source of internet fascination leading into the critically acclaimed sequel's release.

It was a committed transformation for Butler. Getting the Feyd look with black teeth and a creepy bald prosthetic required three hours in the makeup chair.

"It comes over (my head) to my eyelids, covering my eyebrows and everything," says Butler. "Look at the attention to detail on that bald cap with a vein running through it. It's a work of art."

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As the warrior Feyd-Rautha (played by Sting in David Lynch's 1984 "Dune"), Butler packed on 25 pounds of muscle and adopted another noticeable accent. Not the King of Rock 'n' Roll this time, but the voice of villainous ruler Baron Harkonnen (Stellan Skarsgård), who is also Feyd-Rautha's toxic uncle role model.

"The Baron is the one with the most power, so (Feyd) soaked up these traits," says Butler, "For me, it was all about his voice. That changes the rhythm of how you think and breathe."

Villeneuve was all in on the Skarsgård voice, saying, "I deeply love it," Butler recalls. "That's the best note you can get from Denis."

While Butler stayed in Elvis mode while shooting his breakout role, he knew it would be "unhealthy" to live with Feyd-Rautha making "Dune." This is a guy who licks his knife to test his blade before murdering his servant in one unforgettable scene.

"I don't even remember where that (licking) came from," says Butler, who calls the role "an experiment with figuring how to click instantly into character. I knew I had to set a boundary with (Feyd-Rautha) because he's so dangerous. I didn't want to subject my family or Dave to him."

That's important since Bautista and Butler play the most dysfunctional brothers in the Duniverse vying for power and attention. After brutal success conquering the planet Arrakis in "Dune," Rabban stumbles, failing to squash the Atreides-led rebellion in the new film. It's a dark time for a dark man as younger bro Feyd-Rautha steps in to lead and shines, sending Rabban into drinking-fueled rants.

"It's sibling rivalry at its highest peak," says Bautista. "There's a deep hatred that stems from my resentment and insecurity as older brother. Younger brother has always been better, smarter, more loved and more admired."

"So we really despise each other," he says, stressing that the hate stopped with the cameras. "Then Austin and I are talking about lunch. It was effortless."

Even if the actors would not pass as brothers in real life, Villeneuve believes there's a distinct likeness between the two vicious screen characters.

"They are so different physically. But when you look at their mouth structure and overall, there's something there," says Villeneuve. "In the book, it was like Feyd had received all the genes of beauty and Rabban was a more brutal version."

This brother-on-brother brutality peaks when Feyd demands that his failing sibling kiss his foot for dishonoring their house. Butler acknowledges that when he signed up for "Dune," he had not discussed the scene involving Bautista, a hulking one-time WWE star.

"Oddly, that never came up. I never thought that was in the cards," says Butler, before looking at Bautista. "That scene was so wild because I have so much respect for you."

But Bautista reveled in shooting the telling scene.

"A lot of actors would be like, 'I don't want to do that,' " says Bautista. "But I thought it was so great. This is when I get to show who Rabban really is. He's just a coward. Right then, he's put in his place. You might have a moment where you actually feel sympathy for such a despicable character. So, yeah, I loved that scene."

Then it snapped right back to the two actors talking about things like the WWE, a favorite topic for Butler.

"We'd be talking about wrestling. And I'd say, 'You're probably bored with this,' " says Bautista. "But he insisted he was really curious. That meant a lot. He took an interest in me and wanted to get to know me. I can work with someone who makes me feel comfortable."

Bautista and Butler could hug it out each day, even if their despicable "Dune" brothers are in dire need of intensive family counseling.

"On screen, we need an Oprah moment," says Butler.

"I wonder what a Harkonnen therapist would look like," adds Bautista, chuckling. "Because they do need some therapy."