Since 2015, Younger’s Liza Miller has been lying about her age. Played by Broadway favorite and two-time Tony winner Sutton Foster, the 40-something-year-old mother from New Jersey has been passing as a 20-something-year-old Brooklynite. At first, it was to revive her once-career in the publishing industry. But, over the past four seasons, things have gotten more complicated: Liza begins dating a 26-year-old tattoo artist while experiencing unthinkable chemistry with her 40-something boss; but she’s also launched a successful imprint called Millennial with her best friend Kelsey, a rising editor. Her secret has been slipping out over past seasons, but not everybody knows. On June 5, the story continues with the Season 5 premiere—and it’s a doozy.

At the end of the day, Younger (from the creator of Sex and the City) is about its leading lady and the power and necessity of indestructible friendship. We caught up with Foster and her co-star Peter Hermann to talk about their characters’ palpable chemistry, the allure of Liza and Charles, the theatre they’ve been enjoying while filming in New York, and unforgettable theatrical experiences.

I just saw the premiere episode and I am losing my mind. It was a jawdropper.
Peter Hermann: We haven't seen it!
Sutton Foster: We haven't seen it and we're also still filming, we're still shooting and so we're still like in it, and it feels so long ago that we shot the first episode.

Viewers love seeing the two of you in this relationship as it keeps evolving. Fans are adamantly #Team Josh or #Team Charles. People have been cheering for a long time. What is it for you guys that you think makes the relationship between Liza and Charles so special?
SF: I feel like there's this inevitability that's Liza and Charles. It is this thing that they can't...there's this attraction they haven't been able to [realize] and there's this inevitability about them. I don’t know, what is it?
PH: It’s when there's a something-something between two people and there's a part of it that you can't quite name.... I think there are words for as far as Charles is concerned: After his wife left, that's not necessarily the easiest time. Liza enters his life as a light. I think she is the first one to just get her foot in that door of his heart again, and start to pry that open a little bit.
SF: And she's not even trying to
PH: She's not even trying to, it just happens. There's a light under the door, it isn't even open—
SF: That light of possibility. And she's not pursuing.
PH: She's not out looking for a date, you know.
SF: I think Charles is the opposite of Josh. They both provide or bring things into her life that I think she needs or that she desires or she wants. There's something about Charles that she can't [escape]. There's a possibility and curiosity there and she kinda can't get away from it.
PH: And he also sees in her something that he can't quite name. And it's just something uncannily wise beyond her years. And the mystery is delightful.

Filming in New York, you get to go to theatre. Have you seen anything in the past year that you've really loved?
SF: I loved Once on This Island.
PH: I loved Once on This Island, too.
SF: I just loved it. I went bonkers for it. Once on This Island was in the pocket for me. [The year the original production premiered] was the year Secret Garden, Once On This Island, Miss Saigon, and Will Rogers Follies [were nominated for the Tony for Best Musical], and I was 16 years old or something like that. Those were my shows, you know? When I came to New York I saw Miss Saigon and I saw The Secret Garden, I did the national tour of Will Rogers Follies, and I had never seen Once on This Island, but I knew it inside and out, I knew the album backwards and forwards. As soon as I walked into the theatre I was like "what is happening?!" I didn't know how they had transformed the space, and then as soon as the music started, I was like (gasps), and then as soon as I heard "One small girl" I was like sobbing. And I'm like, "I can't deal, I can't deal with this." The best part is that at my Pilates studio, Stephen Flaherty takes the class on Sundays! He takes the class before me or after me, so I see him all the time, and I like attacked him [after seeing the show]. And the best part was that I went, "I just have to tell you that I saw Once on This Island" and he's like, "I just have to tell you, we just binge-watched Younger! I just watched all four seasons!" But I was able to just gush and tell him what an amazing show it was. I just loved every moment of it. That was my favorite thing that I've seen. I was weeping and my husband had never seen it and I turned to him and I was like, "If he doesn't like this, I don't know what I'm gonna do." So dramatic. And I turned to him and I was like, "Did you like that?" And he goes, "I loved it." and I went, "OH THANK GOD."

What about you, Peter?
PH: We just saw Mean Girls and we loved it. It's so hard to have a show with a flat out message—like that show has a message—and not make the audience back up because they're receiving a message. To have the audience hear something about the way we all treat each other, and the way that women treat each other, and about friendship and support and all that, and have the audience lean in, I think that's a very hard thing to do. And I love, I take such delight, as we all do, in watching a cast that loves what they're doing. And holy cow! We had an absolutely fantastic time.

In the realm of musical theatre, there was a Tweet going around that said "You need to play a single Broadway number to your therapist to explain yourself as a person, what's it gonna be?"
PH: It's not Broadway, but I was gonna say "This Is Me" [from The Greatest Showman].
SF: Mine would be the opening number to Into the Woods.

Is there a dream theatre experience you’ve had?
SF: There is a show that’s the reason I do what I do. I saw Me and My Girl when I was 15. They played at the Fisher Theatre in Detorit and there was an understudy on for the main role—so when the curtain fell I heard the entire cast behind the curtain scream and cheer because the understudy had gone on for the first time and I went, “I want to do that.”
PH: I understudied Michael Hayden in Judgment at Nuremberg in 2001 [on Broadway] and the week before previews he had to go on vocal rest. So I get a day-and-a-half notice and went on for a weekend and I performed the role—the role was Oscar Rolfe and it was the role that Maximilian Schell played in the movie in 1962 and Maximilian Schell was in the play [as a different role]. Michael Hayden and I played the role in front of Maximilian Schell that he won an Oscar for. It was phenomenal. He was incredibly kind and he patted me on the shoulder and he said, “Keep going.” It was incredible.

Tune in to Younger on TVLand Tuesday Nights at 10/9c. Catch up on past seasons at TVLand.com and Hulu. And be sure to follow Playbill on Instagram to find out the theatre dream roles for the full Younger cast!