LOS ANGELES, CA.- Christopher Nolan and Robert Downey Jr. have each worked on some of the most lucrative and beloved superhero films of our time, many of them with enormous star-filled casts, so how is it that the two had never worked together on a movie before now, superhero or otherwise?

Their paths crossed, sort of, on “Batman Begins” (more on that later). But it took a different kind of summer blockbuster, a three-hour biopic about the triumphs and travails of a theoretical physicist working in New Mexico in the 1940s, to finally bring them together.

Since its release in July, “Oppenheimer” has amassed nearly $1 billion in worldwide ticket sales, earned critical raves and been nominated for scores of awards, including 13 Oscars. Among those nominations are three for Nolan, 53, for best picture, best director and best adapted screenplay, and a best supporting actor one for Downey, 58, for his performance as Lewis Strauss, the title character’s Salieri-like nemesis. The nominations are hardly their first — counting “Oppenheimer,” Downey has received three, Nolan, eight — but neither has ever won before and now they’re both considered front-runners.

The day after the Oscar nominations were announced, the two got together on the Universal studio lot to talk about how they first met, what winning an Oscar would mean to them and why so many people didn’t notice that that balding, sweaty guy who had it in for Oppenheimer was actually Robert Downey Jr.

These are edited excerpts from our conversation.

Q: This is your first time working together. How did you two meet?

ROBERT DOWNEY JR.: Here’s what I never got to ask you. We met in a lobby somewhere. You were casting, was it “Batman Begins” or “The Dark Knight”?

CHRISTOPHER NOLAN: “Batman Begins” [2005].

DOWNEY: And you knew before I came down for the coffee that I probably wasn’t the guy.

NOLAN: I 100% knew you weren’t the guy. In my head that was already cast. But I always wanted to meet you.

DOWNEY: Is it poor taste to tell me the role that you already knew I wasn’t going to get?

NOLAN: [Long pause] I’m just trying to think if this is a good thing to reveal, or a bad thing.

DOWNEY: Yeah, forget it. I just had a feeling that that was one of those thoughtful yet gratuitous meetings.

NOLAN: No, I was a huge admirer of yours and therefore selfishly just wanted to take the meeting. But I was also a little afraid of you, you know. I had heard all kinds of stories about how you were crazy. It was only a few years after the last of those stories that had come out about you.

Q: How did you get over your misgivings?

DOWNEY: You let 10 or 12 years pass and watch the news cycle.

NOLAN: Exactly. Let Jon Favreau [the “Iron Man” director”] take a huge risk, and there you go. No, the truth is, I think Jon Favreau casting Robert as Tony Stark is one of the most significant and consequential casting decisions in Hollywood history. It wound up defining our industry. Coming out of COVID, you say, “Thank God for Marvel movies.” And it’s one of those where, in retrospect, everybody thinks it was obvious. But he took an enormous risk casting you in that role.

Q: Robert, it sounds like Chris had already heard a lot about you before you two met. What had you heard about Chris?

DOWNEY: I’d heard everything from people who balked at working with him to people who said, “It changed my life.” That’s even weirder, because there’s no actual consensus. But I’ve never seen such efficiency and regard for the privilege it is to make films.

Q: I’m sure I’m not the first person who didn’t recognize you when they saw this film, even though you’re in it quite a lot.

NOLAN: One of the first few times we showed the film, I was talking to a young guy afterwards who had no idea Robert was in it. That’s when I knew that you had completely just lost yourself in this character. But then I thought, well, how’s that going to help sell the movie?

DOWNEY: We weren’t trying to make me unrecognizable. Though you did say you’d like to remove the handsome. And I was like, Christopher Nolan thinks I’m handsome! But it’s not because there’s some transformation I did, or that I’m such a chameleon. It’s that with this film, you’re cold-plunged into this reality in the first act, and all these seemingly chaotic strands come back and tie together in the engine of the third act, so it’s an immensely satisfying three-act, three-hour experience. There’s a lot going on. I think I just kind of happen to slip by.

Q: When you think about Robert Downey Jr., you don’t necessarily think of a guy like Lewis Strauss, this petty, vindictive bureaucrat. Chris, what made you go, yes, Robert Downey Jr. is Lewis Strauss?

NOLAN: You’re always looking to work with great actors, but you’re also looking to catch them in a moment in their lives and careers where you’ve got something to offer them that they haven’t done before, or haven’t done in a long time. I just really wanted to see this incredible movie star put down all of that baggage, that charisma, and just lose himself in a dramatic portrayal of a very complicated man. I always wanted to work with him, really. Once I stopped being afraid of him.

Q: I imagine Chris’ screenplay helped.

DOWNEY: It was all there. But then I get easily distracted, bored is the wrong word, so he would let me embellish here or there. And once in a while he would remind us about the timing. He wouldn’t necessarily say go faster, he would say, “Remember …

NOLAN: … it’s a long movie.”

DOWNEY: “It’s a long movie, so, you know, be advised.”

Q: In the film, there are graphic descriptions of the aftermath of the bombings of Hiroshima and Nagasaki. Why did you choose not to show any of that?

NOLAN: There were a lot of different issues that fed into that decision and the way we planned the portrayal. The key underlying thing is that what’s most powerful in cinema is often what is not shown. You’re asking the audience to use their imaginations. It’s something that people who make horror movies completely understand, that less can be more. Watching Cillian [Murphy, who plays Oppenheimer] listen to some of these things is one of the most moving experiences for me, because he’s taking you on that journey.

Q: The film has obviously done well. But was anyone telling you early on, “I’m not sure if a three-hour movie about J. Robert Oppenheimer is going to bring people in”?

NOLAN: Oh yeah. They were saying that to me until the night it opened. So that opening weekend was thrilling. The numbers coming in were defying all of our greatest hopes. We always have done well putting challenging material out there, but it was a complete shock for Emma [Thomas, one of the film’s producers, who’s also his wife] and me the level at which it worked. Because we’d made the film very efficiently.

DOWNEY: Fiscally responsible event cinema. It almost laughs in the face of what I grew up in: the ’80s, bloated, big-budget behemoth that you go, “It doesn’t matter, because they’re still going to double their money.”

Q: What did you learn from working together?

DOWNEY: That I had an incomplete education.

NOLAN: I already knew that Robert was great, and if we could just get him in that room, he would kill, and he did. But I also learned that the source of that greatness is his generosity. He listens, and he considers everybody around him creatively.

DOWNEY: I don’t want to put words in your mouth, but I think you learned that it’s kind of nice to socialize with your actors on location once in a while.

NOLAN: No, that’s [expletive]. He made me go out to dinner, and he was like, “See, this is great! Isn’t this great?”

Q: The film just got 13 Oscar nominations. With all the buildup and early predictions, though, maybe it wasn’t such a surprise?

NOLAN: It was definitely a surprise. You never know what’s going to happen.

DOWNEY: It’s a weird thing, particularly when it’s one of the early a.m. ones. You don’t want to be that person who’s setting your alarm and waiting with bated breath.

NOLAN: I slept through them. I didn’t want to jinx anything by setting the alarm and waiting. I figured if anything happened, someone would call me.

DOWNEY: But you’re not a jinx guy.

NOLAN: No, I am! I am very superstitious. I mean, I’m nowhere near as superstitious as you are. But I respect the jinx enormously.

Q: What would it mean to you if you won the Oscar?

NOLAN: I grew up watching the Oscars. I’ve always loved Hollywood, Hollywood movies, studio films, all of that. So, yeah, it would be a dream come true.

DOWNEY: Things are so weird now compared to the way it was 30 years ago, when I was doing my first little mini round for “Chaplin” [1992, which earned him a best-actor nod]. I remember thinking there was a lot of free time in my schedule. No one on my team was imagining that I should expend too much energy because the award was kind of in the bag for [Al Pacino in “Scent of a Woman”]. But to me, I just thought, this is a pretty light schedule making a run at best actor.

Q: What is it like to be the favorite this time, when maybe, as you said regarding Pacino, you haven’t always been?

DOWNEY: It’s hard to say anything that doesn’t make you kind of sound like a [jerk]. Here’s what I do want to say. I think we would agree in general that something happened this year that has reestablished a wide range of filmed entertainment genres being accepted and reembraced. Maybe not as many as we were used to, but certainly enough to keep the shop open.

Q: Do you enjoy awards season, or is it more just something to get through?

NOLAN: [Long pause] It’s a strange process. It’s not terribly natural to me. I enjoy making films more than I do promoting them, like a lot of filmmakers, I think. But at the same time, it’s really wonderful when people respond to the movies. You make the film for an audience, we put it in theaters for an audience, and awards season is one of the ways in which you’re told that you’ve connected with people.

DOWNEY: I love this season! Because you never forget your third time.

This article originally appeared in The New York Times.