Actors not landing the roles they audition for can still lead to them getting cast in a different part. Tom Hiddleston tried out for Thor, and ended up playing Loki with great acclaim. Recently, Nicholas Hoult landed the role of Lex Luthor in Superman: Legacy, even though he originally auditioned to play the Man of Steel–and even tried out for Batman at one point for Matt Reeves. Cillian Murphy had a similar career trajectory as he auditioned for Christopher Nolan’s Batman Begins to play the Dark Knight, even donning Val Kilmer’s old Batsuit for the audition.

While he didn’t make the cut for Batman, Murphy ended up working with Nolan throughout his Dark Knight trilogy as Dr. Jonathan Crane, the Scarecrow. It would also lead to a 20-year career journey with Nolan which recently helped Murphy earn his first Oscar nomination in Oppenheimer. The Oscar-nominated director and actor spoke to Deadline, with Nolan explaining why he inevitably went with Christian Bale over Murphy, but also what makes him a fascinating actor.

“I don’t think he had the physicality at the time,” says Nolan. “We tested everyone as Bruce Wayne and we tested them as Batman, and the thing that Christian had that was so striking was that he understood that so much of acting is about reality. So much of acting is about emotional truth. And when you put on a costume like the Batsuit, you have to become this icon. Christian had this crazy energy that he just directed. He’d figured out how that worked and what that would be–the way Bruce Wayne does in the film. He adopts this persona. It’s a very specific thing. And he tore a hole on the screen as Batman. It was like, there was no question.”

Nolan would direct Bale two more times as Batman and then in the 2006 sci-fi suspense thriller, The Prestige. Though it’s been over 10 years since Nolan has worked with Bale, he’s worked with Murphy three more outside of Gotham City: Inception, Dunkirk, and Oppenheimer–the latter two earning Nolan Oscar nominations for Best Director.

The director continued to Murphy saying that watching Peaky Blinders and the character of Thomas Shelby is intimidating in his own way. “That’s an iconic character with an oppressive presence, where he walks into the room, and everything goes quiet, and he owns that space. In the way Batman does, or an iconic character of that kind. There’s a physicality that’s extremely confident and strong in everything he does, in every gesture,” he said. “Is that a conscious thing you’ve developed over the years, or was it just looking at that part and thinking, ‘How do I do that?'”

Murphy said he thought it was both. “I also think I felt, back then, that that was a part I hadn’t really explored before, that kind of physically imposing character. I’d never been offered those parts. But I always think, Chris, that one of your underrated strengths is casting. Everyone knows all of your amazing strengths, but you cast things exquisitely. And I think the Scarecrow was the right part for me to be in at that time in my career.”

Before Oppenheimer’s release, Nolan spoke about not casting him in the role at the time and how Murphy broke the supervillain mold.

“Everybody was so excited by watching you perform that when I then said to them, ‘Okay, Christian Bale is Batman, but what about Cillian to play Scarecrow?’ There was no dissent. All the previous Batman villains had been played by huge movie stars: Jack Nicholson, Arnold Schwarzenegger, Jim Carrey, that kind of thing. That was a big leap for them and it really was purely on the basis of that test. So that’s how you got to play Scarecrow.”

Oppenheimer is nominated for 13 Academy Awards including Best Director and Best Actor for Nolan and Murphy, respectively. You can watch the Academy Awards live on March 10.