Co-written by show creator Julian Fellowes (Downton Abbey) and Sonja Warfield, the HBO drama series The Gilded Age is set in the lavishly extravagant world of late 19th century New York and finds the orphaned Marian Brook (Louisa Jacobson) moving into the home of her aunts, Agnes van Rhijn (Christine Baranski) and Ada Brook (Cynthia Nixon). Once there, the young woman quickly learns the importance of whether you come from old money or new and that there are certain expectations for her that she might not be fully willing to follow, as she finds her place in society.

During a virtual junket for the new show, co-stars Baranski and Nixon spoke to Collider about how the relationship between their characters is similar to that of an old married couple, how Ada is overflowing with love while Agnes has other things to concern herself with, what Marian’s arrival means for them, and whether they get nervous when starting on a new project.

Collider: I love the relationship between your characters so much. They have some very big differences between them, but they also clearly love each other and look out for each other in ways that only family can. What do you love about getting to explore the dynamic between these two women?

CHRISTINE BARANSKI: For me, I remember someone saying to me that the hardest thing to portray is a marriage because there’s such familiarity with a married couple and so many patterns that just repeat themselves, like a musical piece, and they’re very subtle. If you listen to married couples, you can hear the quality of banter and the little subtle criticisms, and it’s not the first time this has been said, it’s maybe the 10,000th time. Anyway, I think of Cynthia [Nixon] and I, and we say this about the relationship, like an old married couple. I love refining that and making it as subtle and natural as possible. There are these old wounds that get rubbed, and these old grudges and old histories, and it repeats itself. It makes for wonderful comedy. The relationship is quite funny, and recognizable as older sister, younger sister.

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Image via HBO

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Cynthia, do you ever feel like your character is just going to have a moment where she just breaks and has an outburst?

CYNTHIA NIXON: The power differential between these women is significant. Not only is she the older sister, not only does she have more of the powerhouse personality, but she controls all the purse strings. Ada is living there on her charity, essentially. Ada has discovered a long time ago, maybe even when they were still children, that the way to win over Agnes is not to assault her directly, but to go around behind and work behind the scenes. I think we see that very much still in evidence. So never say never, but I think that Ada has her own way of fighting, and it’s far more of a guerrilla warfare than a full-out frontal attack.

That’s why I love her relationship with her dog because it just feels like it’s this comfort animal that she has that keeps her from just totally having an outburst sometimes.

NIXON: That’s one of the things about Ada, she has so much love. She’s just overflowing with love. It’s why she’s so excited that Marian is coming. She wants someone to love. And she loves Agnes very much, but Agnes doesn’t wanna hear about love. Agnes has bigger concerns.

You guys have both been in this business for a while. You’ve played a variety of characters on all different types of projects, and you’ve played characters before that you’ve gotten to live in for a bit on other TV shows. What’s the first day on a new job like for you guys? Do you always get nervous? Are you always just excited? Is it somewhere in between? What’s it like, every time you start something new?

BARANSKI: I’m nervous, particularly on a show of this size. It’s HBO, Julian Fellowes, a huge cast and a period piece. Yeah, it took me a while to settle in. That said, when you’ve been working long enough as an actor, I think you recognize fear and you’re a little better at negotiating it and not letting it choke your work. You know how to take a few deep breaths or just look into your partner’s eyes and just get past yourself and concentrate. You have developed more of a skill set for managing your nerves. But honestly, it’s hard when you’re filming. We had some really big scenes that we filmed, right off the bat, and they were heavy with words and dialogue, and we had to create that relationship. It’s not like the theater, where you have four weeks of rehearsal plus previews. It’s gonna go on film and we’re gonna see it. There’s that tightrope quality that I always find daunting about film. You’re lucky if you get a second chance or a reshoot. Rarely do you get a chance to film it again. But yeah, in a word, yes. I get nervous. I don’t know about Cynthia.

NIXON: Yes, I think the first day is really hard, and with a cast so large. Once we had found our footing, then there were just more and more actors that would come in, in different scenes, and often they were people that Christine and I knew previously, or had maybe worked with previously. I would always be excited when the new people would show up. Again and again, I would relive it and see how nervous they were. I would say, “It’s just because it’s your first day. I promise you, by day two and certainly by day three, you won’t even remember that you used to be nervous. You just have to get through that first day, or maybe two.”

BARANSKI: It’s very true. The first day is an out-of-body experience.

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Image via HBO

Christine, the line of dialogue that most stood out for me in the episodes that I’ve seen is when Agnes says, “I’m not concerned with facts, not if they interfere with my beliefs.”

BARANSKI: That’s a wonderful line.

It’s so great. Not only does it perfectly describe Agnes, but it also sounds so familiar to similar statements we’ve been hearing the last few years now.

BARANSKI: Doesn’t it? That’s Julian. I take no credit for that line. All I had to do was say it with conviction. But Julian Fellowes, what a marvelous remark from someone like Agnes. But you are right. There are lot of people who wouldn’t be clever enough to say a sentence like that, but who actually think that, and they’re standing in the way of a great deal of progress in our country.

Do you feel like Agnes is a character who will ever be open to change?

BARANSKI: That’s Julian’s decision. That’s a creative decision. I think she’s an intelligent woman. You see her relationship with Peggy, with the young Black woman who has high hopes, and you see Agnes is capable of wider thinking. I think the character has enormous potential, but she’s justifiably horrified about what’s going on across the street from her, and she’s very nervous about what is happening to the world, if it’s only going to be defined by money or engulfed by money.

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Image via HBO

Cynthia, do you feel like Ada has dreams for herself anymore, or is she encouraging Marian to be the one to go out and find those dreams that maybe she didn’t have the chance to fulfill?

NIXON: I think that Ada is so thrilled with Marian’s arrival and hopes that she might be kind of a surrogate daughter for Ada. But I think she is also very vicariously living through her, and trying to redo her own life and some of the mistakes that were made. I think the thing about Ada is she’s excited about the changes that are happening, and she wants to, at the very least, be a spectator of them. But I think that Ada is a very humble person who doesn’t ask for much, and has been taught and learned not to ask for much, so she doesn’t think of her own dreams. But who knows? Maybe some undreamed dreams might materialize for her.

The Gilded Age airs on Monday nights on HBO and is available to stream at HBO Max.