Performers taking part in our Actors on Actors conversations usually come prepared. But Patricia Arquette has done more than her share of homework when she walks into a Hollywood studio on a Sunday afternoon to interview Julia Roberts. Arquette, who jokes she wants a career pivot to hosting a talk show, has scribbled detailed notes on a sheet of paper — and goes one step further in the green room, asking Twitter followers to submit questions too.

A late-night interview show may not be out of reach for Arquette. Once on camera, she conducts one of the more probing interviews of the weekend — with a little help from her 300,000 or so social-media friends. “Now, do you know any of these people?” Roberts wonders as Arquette starts reading from her phone.

“No, I don’t,” Arquette says. “You’re a loved woman. Deal with it.”

Really, both of them are. Roberts and Arquette have both won Oscars and every other award known to woman­kind. And they proved that they retain the capacity to surprise. Arquette went dark, first as a prison employee involved in a breakout on Showtime’s “Escape at Dannemora” and then as a villainous mother on Hulu’s “The Act.” And Roberts, among the last holdout movie stars to make the leap into television, found a project worthy of her dramatic chops, as a therapist at a facility for war veterans on Amazon’s “Homecoming.” TV may have been a new frontier for Roberts — but she took to it as easily as Arquette did to interviewing.

Patricia Arquette: I have a funny story.

Julia Roberts: OK.

PA: So many, many, many years ago, one of my early auditions was for a movie called “3,000.” Most people don’t know that “3,000” was the original “Pretty Woman” script. And the ending was really heavy.

JR: Threw her out of the car, threw the money on top of her, as memory serves, and just drove away, leaving her in some dirty alley.

PA: Right. So it really read like a gritty art movie. When you first read it, it was that incarnation.

JR: I got the part in “3,000.” I love that you’re asking me this question, but I had no business being in a movie like that. This small movie company folded over the weekend, and by Monday, I didn’t have a job.

PA: Wow.

JR: There was one producer that stayed with the script, and it went to Disney. I thought, “Went to Disney? Are they going to animate it?” Garry Marshall came on, and because he’s a great human being, he felt it would only be fair to meet me, since I had this job for three days and lost it. And they changed the whole thing. And it became more something that is in my wheelhouse.

SHAYAN ASGHARNIA for Variety

PA: I never knew any of that. But I also had a fantasy of recasting you in “3,000,” the original script, and you could even do it now.

JR: I couldn’t do it then. I couldn’t do it now. Thank God it fell apart. Even in “Pretty Woman,” if I had to be in a slip, I’d be covered in hives. I was breaking out in a cold sweat watching “Escape at Dannemora.”… Oh, my Christ. I just don’t even know.

PA: For me, I’m completely the opposite in my personal life. I take baths in the dark often, really in real life. So I’m really uptight, and yet I’ve played several parts that are very sexually more free than I am, and comfortable. For me, when I was looking at the sex scenes in “Escape at Dannemora,” it was like, “I’m going to gain all this weight. It’s going to be the first time I’m ever not going to use body makeup.” I want to move away from myself and have the conversation: What kind of body types are acceptable? Who’s sexy, and who gets to decide who’s sexy?

JR: Well, you were hot as a pistol, and very compelling, but … Do you break for lunch after that? Where is everybody? Who’s standing there?

PA: What I have found in these parts that have been more sexual, there’s always this coven of women from the wardrobe department and makeup people. They’re there with robes. They don’t even say anything, but they’re like, “We’re here.”

JR: Yeah, you just feel it.

PA: So you feel this strength from women, and even male allies were like, “Yeah, we’re not going to have any monitors around the set.” I had to do this one part with David Lynch, and I was going to have to walk around totally naked in the scene, and I was so uptight. And I said, and maybe I could get sued for this now, “I’m going to take off my robe. If I turn around, and I see you, and you don’t need to be on this set, I’m going to punch you in the face.”

JR: Well done.

PA: So all of a sudden, about 40 people went scattering off into the desert.

JR: And if you said, “I’m going to punch you in the face,” I believe that you would punch them in the face.

PA: But I think part of my survival mechanism is also talking with the other actor about what’s emotionally going on for these people right now, our characters. I have more questions for you.

SHAYAN ASGHARNIA for Variety

JR: OK. You have your paper. It annoys me, and you’re the only one that gets away with it in my heart. Your speeches are always great, and then you have some little caboose that you bring in just before you walk off. “And, by the way, there’s also this I want you all to think about.” I love when you do that.

PA: Early on, you were the highest-paid actor in Hollywood. How did that feel to have that conversation happen? Did it feel like pressure, breaking that glass ceiling?

JR: It never felt like pressure. All the salaries in those days where there was just a lot of money to be spent making films — in a comical way, I thought, OK, sure, this is ridiculous, but I’ll be part of this party. I’m just walking in a path that Barbra Streisand has hacked out with a machete, so to be the gardener that’s picking some weeds that have come up since these incredible women before me have made a path for all of us to be artists in our own right — it was nice to feel that I had a little puzzle piece to that.

PA: You went from doing these gigantic movies and then started taking little movies that you’re basically getting scale, right? So that must’ve been a conscious choice for you.

JR: I think the big moment in my career was when I had done a lot of films in a row. I think it was after I did “Sleeping With the Enemy,” and I saw some really great actors that I admired what they were doing. And then there were a few movies that I thought, “Why is she in that movie? She’s better than that narrative.” I just had this instinct to stop doing anything if it didn’t feel that passionate.

PA: Your new show, “Homecoming,” is an interesting emotional departure. A lot of people see you oftentimes as …

JR: Much nicer?

PA: Well, you have this beautiful way of breaking the moment with humor, but this character is really kind of darker.

JR: It was a dream job pretty much from start to finish. If someone asked me to be with that same group over and over and over, I wouldn’t hesitate. You want youth, and innovation, and just a new point of view. And we had all those things in abundance, as a collective. For me to come into a television show … The first production email I got, I thought, why do I not understand what this is telling me? Thirty years of call sheets and production emails, how do I not understand what this is telling me? It’s just different nomenclature. We filmed it like a movie in two parts. Is that what you did on “Medium”? Because you were on that show a really long time.

PA: “Medium” would often be written the night before.

JR: How would you do that?

PA: Sometimes I didn’t ever get a full script. It was crazy-making. I was like, “Ah! Who’s the bad guy? What’s happening?”

JR: We had time, and a strange alchemy. So much credit has to go to Sam Esmail, who was our director of the entire show. The first three days of shooting, I’m so nervous, and wanted to do everything right, and make a great first impression. And Stephan [James] and I, we’re letter perfect. And we wrapped the day’s work before lunch on the first day. We knew our goals collectively, and there was a momentum that I thought was kind of extraordinary.

PA: I was back here at the break room, and I said, “Who’s got a question for Julia Roberts?” And I thought, why don’t I just tweet that out? If you had one question for Julia Roberts, what would it be?

JR: Did you really do that?

“All the salaries in those days — I thought, OK, sure, this is ridiculous, but I’ll be a part of this party.”

Julia Roberts

PA: Yes, I did. Let’s see. Somebody was asking, what’s your favorite classic film?

JR: My favorite comedy would be “The Philadelphia Story.” My favorite drama would be “Now, Voyager.” Bette Davis. What’s your genre?

PA: I do tend to like darker material.

JR: I can see that in you.

PA: I’m a dark-type-of-attitude person. Two of the performances by women that made me want to act were Jessica Lange in “Frances,” and Gena Rowlands in “A Woman Under the Influence.” But my favorite film is F.W. Murnau’s “Sunrise,” from 1927.

JR: You’re complex. I like that. You are not sunshine and kittens.

PA: You were called America’s Sweetheart. How did that feel?

JR: This went very Barbara Walters. I am very unemotional about stuff like that. I don’t feel that I have to live up to something. But I’ve never been a person that attracted musician energy, where people see a musician in the grocery store, and you go, “Oh, my God.” I get this kind of energy, like, “You cut your hair. It still looks cute.” What do people say when they come up to you?

PA: Well, sometimes they say, “You look a lot like Patricia Arquette, but she’s taller than you.” I get that. “You really freaked me out on ‘The Act’” or “Thank you for making me think of people like Tilly in a different way,” from “Escape at Dannemora.” When you think about acting, what do you love about acting?

JR: I think all of it. Just all of the circus. The hours, that you work so hard to not live in a trailer so that you can then find a job where you live in a trailer. There’s an irony to that. Did you start off in L.A. or in New York?

PA: I was in L.A., and I have a terrible audition story. I had this audition for this movie. It was for this Italian girl drummer in the band. So I put this temporary rinse in my hair that was very dark.

JR: That’s what I did for “Mystic Pizza”! We’re the same person. I’m the tall you, and you’re the petite me.

PA: But you are the successful version of me, because I went to the audition, and they said, “Let’s do the dance part.” I’m like, ”What dance part? I thought it was a band.” I’m bumping into girls.

JR: You’re kicking girls. They think you’re trying to take them out one by one.

PA: And now I’m sweating, and the fake hair dye is pouring down my white tank top, and I look miserable. It’s all over my face. I was just in this flop-sweat nightmare.

JR: I had a success out of it, but I did have about two cans of colored mousse that I got at Lamston’s Drug Store. My hair was stiff as a board. Leaving the subway after the audition, I had on my white blouse, walking from the subway in the rain with two cans of dark mousse just running down all of me.

PA: That’s really surreal. Here we are, knock on wood. We’ve had success in our careers, and we have these crazy audition, dripping-dye stories.

JR: And now we’re just rad 51-year-olds with naturally blond hair.