Even the now-Oscar-winning film editor behind Oppenheimer wasn't initially sure the subject matter would be interesting enough to sustain a three-hour runtime.

Backstage at the Academy Awards on Sunday, after winning Best Editing, Jennifer Lame told reporters, "I have to be honest, when I read the script, and from what I know about [Oppenheimer, the man], I couldn’t imagine how this could sustain for three hours. Nobody knows him, and he's inscrutable, and he’s kind of boring?"

Lame was responding to a question about what it was like editing the scenes involving Oscar nominee Cillian Murphy, who stars as the titular J. Robert Oppenheimer. "Cillian brought this intensity to it," she continued. "I was just mesmerized by this performance, and you wanted to know who he was."

She noted some of her favorite scenes, including when Murphy's Oppenheimer is in President Truman’s office and he's fumbling to make a sentence, as well as when he appears opposite Casey Affleck. "There were so many of my favorite scenes with Cillian that I did have to cut down because he’s just fantastic," she added.

The Academy voters certainly feel the film was worth the three hours in a theater. The film has been a clear frontrunner in the awards season race, scooping up major honors over the past few months. On Sunday, Robert Downey Jr. won a major Oscar victory, receiving the award for Best Supporting Actor.

"I'd like to thank my terrible childhood and the Academy, in that order," Downey Jr. said during his acceptance speech. "I'd like to thank my veterinarian — I mean wife, Susan Downey — over there. She found me a snarling rescue pet, and you loved me back to life. That's why I'm here. Thank you."

In her own acceptance speech, Lame thanked "bad-ass producer" Emma Thomas, the longtime filmmaking partner and wife of Christopher Nolan. As for Nolan himself, Lame joked, "You're okay too."

The 96th Academy Awards aired Sunday, March 10, on ABC. See the full list of 2024 Oscar winners here.

With reporting from Lauren Huff.

Check out more from EW's The Awardist, featuring exclusive interviews, analysis, and our podcast diving into all the highlights from the year's best in TV.