Cillian Murphy Wins Best Actor at 2024 Oscars, Dedicates His Award to 'Peacemakers Everywhere'

The 'Oppenheimer' star completed his awards season sweep during Sunday's Academy Awards.

He became death, the destroyer of worlds, and now, he's also an Oscar winner!

Cillian Murphy completed his awards season sweep on Sunday, winning Best Actor at the 96th Academy Awards for his starring role as physicist J. Robert Oppenheimer -- the theoretical physicist credited as the "father of the atomic bomb" -- in Christopher Nolan's Oppenheimer.

After Ben Kingsley introduced the actor, praising the actor as "masterful" and "riveting," Murphy took the stage to accept the award.

"I'm a little overwhelmed," Murphy admitted, before thanking the Academy, the cast and crew of Oppenheimer, his fellow nominees and his family. After pointing out that, for better or for worse, we're living in the world of the atomic bomb, Murphy dedicated his award to "peacemakers everywhere."

Kevin Winter/Getty Images

Prior to Sunday, Murphy had already won the Golden Globe, the BAFTA, and the Screen Actors Guild Award for his groundbreaking role. Plus, the star-studded Oppenheimer cast -- which also includes Robert Downey Jr.Matt DamonEmily BluntFlorence PughKenneth Branagh and more -- won ensemble awards at both the SAG and Critics Choice Awards.

The actor opened up to ET about his experience making the film in an interview last summer, prior to the record-breaking "Barbenheimer" opening weekend.

"The extraordinary thing about the script was it's written in the first person, which is the first time I'd ever encountered that," Murphy shared of his first impression. "You realize then this is something different. They made this very clever thing in the movie -- the Oppenheimer sequences are in color, and then the Strauss sequences are in black and white. So it's kind of subjective-objective, and that's just amazing."

Downey referred to Murphy's transformation in the film as a "heroic effort," but Murphy humbly attributed his portrayal to the "safe environment" Nolan created for his actors on set.

"He creates this really kind of like a laboratory, where you can just try stuff out and he just lets you off," he explained. "And the other thing is, I was thinking about it, no scene ever gets left behind, do you know what I mean? No scene is less than another."

The 2024 Academy Awards, hosted by Jimmy Kimmel, airs live from the Dolby Theatre in Los Angeles on Sunday, March 10, at 4 p.m. PT/7 p.m. ET on ABC. Follow along at ETonline.com for full Oscars coverage, including red carpet arrivals, the complete winners list and more.

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