Jennifer Nettles Had Sung ‘She Used to Be Mine.’ But Not While Crying.

Sara Bareilles and Jennifer Nettles have been friends for over a decade, and Nettles had long been itching to step into Bareilles’s musical “Waitress.”

“For years we kept trying to make it happen but it never worked on the logistics side,” she said in a recent video call.

Everything finally fell into place this fall, and on Wednesday Nettles, who is most famous as half of the Grammy-winning country duo Sugarland, wrapped up a five-week run playing Jenna, a pie-making wiz dealing with an unexpected pregnancy, in the show, as it returned along with Broadway itself.

“It’s a beautiful, sacred space, and Broadway is such a community,” Nettles, 47, said of finally getting to tie on Jenna’s apron. “It was very poignant to be in this show for this reopening.”

Bareilles was happy to see Nettles connect with her show as well, and with the song “She Used to Be Mine.”

“Jennifer so clearly knows who Jenna really is,” she said by email. “I watch my friend disappear onstage and I see only Jenna’s complexity. Her final moments in ‘She Used to Be Mine’ are some of my favorite of all time. She digs down deep and does not come up for air, connecting the musical phrases as her character finds her strength.”

Seeing Nettles thrive on Broadway may surprise those who only know the singer-songwriter from Sugarland or her thriving solo career. But “Waitress” wasn’t Nettles’s first show-tune rodeo. She played Roxie Hart in “Chicago” in 2015 and Donna Sheridan in “Mamma Mia!” at the Hollywood Bowl two years later. In June she released a collection of musical-theater numbers titled “Always Like New.”

She also has a burgeoning screen career with roles in the movie “Harriet” and as the matriarch of a televangelist family in the HBO comedy “The Righteous Gemstones.”

The effervescent Nettles spoke about becoming a mom, sensible shoes and, er, poison from her dressing room at the Ethel Barrymore Theater, shortly before one of her last performances in “Waitress.” These are edited excerpts from the conversation.

You’ve loved musicals since you were a kid. Why did you end up choosing country music?

All the way through high school and college I was able to do both because there were programs and community theater. I started having traction in music in college and had that fork-in-the-road moment, and I thought, “Music has some momentum, I’m going to go over here.” But I always longed to be able to do both, and I was just one person [laughs].

When did you start planting the seeds for a turn to musical theater?

Around 12 years ago, I was going to do Elphaba in “Wicked” on tour and then make my way to Broadway. But I was dealing with a ton of acid reflux at the time, before we really knew that was such a thing for singers. I was really, really stressed and I pulled out because I didn’t know what was going on with my instrument. The right thing always happens at the right time, you know, and in 2015 I was able to enjoy going right to the Broadway stage in “Chicago.”

Between the new album and Broadway reopening, did it feel like musical-theater serendipity for you?

I had been recording “Always Like New” over the course of 2019 and we recorded the last note of the last song on March 12, 2020. I walked out of the vocal booth and our phones started lighting up, saying Broadway was closing. I put the record out in June and that felt sort of like waving this flag of, “OK, we’re coming back,” because we knew of the plans of hopeful September reopening. So to move from an album I’ve always wanted to make to stepping on to the very stages that inspired it — artistically that felt like this is how it’s supposed to be.

What’s your take on Jenna?

The journey of motherhood, for me as it is for some women, was such a confluence — I have jokingly called it a bludgeoning of identity. I was never one of those women who thought she always wanted to have kids. I was open to it and I love children, but I already had another purpose. The loss that happens to everybody but specifically to mothers who have a pre-existing job purpose outside of family — the loss was extreme. The gains were beautiful, too, don’t get me wrong, but both of your hands are full in motherhood: There is sacrifice and loss and death, and there is birth and beauty and fullness. I relate to Jenna as a woman, as being Southern, but that transformation where she’s just like, “Wow, what is happening to my life? Who am I? What do I want?” is so accessible to me.

You have done Jenna’s showstopper, “She Used to Be Mine,” in concert. What was it like singing it in the show?

It’s so different. In concert you’re just doing it as a piece of music. To do it within the character and within the arc, and that being her 11 o’clock moment. Performing while crying is its own animal.

Did you look forward to the number or did you dread it?

Once I figured out how to sing it and act it and cry it and scream it all at the same time, I actually did look forward to it. So much tension has been building for her this whole time that to allow for that release is very cathartic every time I do it.

At least you got to do it in sensible shoes.

Thank you, Lord! I’m glad she is a waitress and able to wear those shoes, that’s for sure.

What’s going through your mind as you are wrapping up with the show?

I wish it could have been longer but in some ways it’s just the right-size bite, you know? I would rather leave still a little bit hungry than over-full and like, “Get me out of here!”

You’re writing the score for a new musical inspired by Giulia Tofana. What can you tell us about her?

She was a slow poisoner in the 17th century. She’s attributed with what they call the first Italian divorce, where she helped women get out of their marriages by killing their husbands [laughs]. Which just makes it fun.

It’s definitely a different career path from pie or country music.

And to be able to tell a story of a woman who isn’t this 20-year-old ingénue! I have gone into way darker transformative caves as a woman in my 40s than I ever did in my 20s. The stakes are higher. This isn’t some budding hero’s journey — this is a blossoming warrior’s journey. Very different. It is also a warning that we still have very far to go where women are concerned. Sexism has been so delicately woven in that, oftentimes, we don’t see it and we think, like, “Oh, we’ve come so far.” Have we? So I am excited to tell this story — to celebrate her, to offer conversation, provocation.