As we’re now in the heart of the holiday season, the major movie studios are rolling out the latest crop of “tentpole” movies, aimed at drawing family audiences to their films in the busiest movie-going days of the year. Disney’s latest offering, Frozen, hits theaters today. Frozen equally honors and reinvents the tradition of Disney fairy tales, and deserves the success and acclaim of modern Disney classics The Little Mermaid, The Lion King, and Aladdin.

The heart of what made the films deeply well-loved was the music. For Frozen, Disney enlisted the talents of husband-and-wife songwriting team Robert Lopez and Kristen Anderson-Lopez. Robert won Tonys and numerous other awards for Avenue Q and The Book of Mormon, before the couple began working together on a number of animation projects including 2011’s Winnie the Pooh. In Frozen, their songs including “Let It Go,” “Do You Want to Build a Snowman,” “For the First Time in Forever,” and “Reindeers Are Better Than People” are the perfect fit for this funny and resonant story with a voice cast that includes Kristen Bell (TV’s Veronica Mars), Idina Menzel (Rent), Jonathan Groff (TV’s Glee), and Josh Gad (Jobs). I recently enjoyed a fun and insightful chat with Robert and Kristen, and they took me deep into the process of writing the song score for Disney’s latest outing. Here’s what they shared with me about putting their spin on the Disney princess genre, balancing a writing partnership and a marriage, and crafting the songs of Frozen.

Jackson Truax: Bobby and Kristen, you both have impressive resumes, individually and collectively. How did you come to be partners, both in life, and professionally?

Robert: We met at the BMI Musical Theater workshop, which is a workshop in Manhattan for songwriters of musical theater. I asked her out. And we started dating We weren’t working together, for a while. There were a few little songs here and there. She kind of was my inspiration for Avenue Q –

Kristen: The Kate Monster song… “There’s a fine, fine line, between love and a waste of time,” is one of the lines that I gave him when we broke up the second time. Because he [kept saying], “I’m too busy. I have my work. I have my work.” I [said], “It’s a fine, fine line.” And he wrote a song about it. And that’s how he got me back.

Robert: When we started working together, it was just for fun. Then we did Finding Nemo – The Musical. Then we did Winnie the Pooh. Each project became a labor of love for us… We felt like we were writing about our own family. This project was no different. They brought us Frozen. They brought us these pictures of the girls. The two princesses (Anna and Elsa) when they were kids. We have two daughters. It just immediately spoke to a movie about sisterhood.

Kristen: They even looked like our daughters. The age separation was about the same. You saw the older one throwing snow up into the air. And the other one looking on…like she was a superhero. And I [thought], “That’s the dynamic, of having an older sister and a younger sister.” As the referees in that dynamic, we know that very, very well. We were excited. We just tapped into it. And said, “There’s a lot of emotion here that we would like to write about.”

JT: The relationship between any writing partners can be challenging. How do you balance that, with not only being married, but also parents?

Kristen: We have specific hours, mostly. And now we have a situation where our studio is in the basement of our house. And the girls know not to come until 5:30pm, if we’re working. Then, as we go up the stairs, we switch hats. But the skills are very similar. The skills that you need to sustain a marriage for ten years, as we have. Things like, winning a fight is not really winning. Sometimes you have to not win a fight –

Robert: But arguments lead to a better product. And everybody wins. When two people are able to communicate, even if they have clashing points of view. You get to a point where everyone’s happy. Which is kind of what you need to do in a marriage, too. And then collaborating as a team, with others, it’s all about communication. And that’s the skill you need for both houses.

Kristen: And I think with marriage, you know them so well. You’re able to say, “I know what this is about. I know we’re arguing over what Anna (Kristen Bell) is saying right now – “

Robert: But you’re just hungry.

Kristen: Or you’re upset because your Mom is blah blah blah blah. We have that knowledge that I think breaks down, sometimes, other collaborations. I know in some of my other collaborations, I don’t have that intimacy of knowledge. And I don’t have the ability to say, “Okay. You’re hungry. And you’re being a pain in the ass right now.” That would turn into a giant fight with some of my other collaborations. And so you have to be a little more polite. And sometimes that means you can’t go as deep.

JT: Robert, I have to ask the burning Avenue Q question. The play is so sweet and moving, but there’s a lot of satire and suspension of disbelief. “There’s a Fine, Fine Line” is the most emotionally resonant song in the score, and ends the first act. Was there ever a concern about ending the first act on the play’s most dramatic note?

Robert: I think in any musical form of storytelling, whether it’s a movie with songs like Frozen, or Avenue Q, you have a certain expectation from the audience. And one of the best things you can do, is to subvert that expectation. With a show like Avenue Q, people are expecting it to be like Sesame Street on crack, or whatever. And then when you give them the emotion, they’re not expecting it. It challenges expectations. I think with this movie, people are expecting something that they’ve seen before. And what we tried to do was –

Kristen: Subvert. Subvert some of the expectations the audience has about what Disney princesses are like. Making Anna funny, was just sort of subversive in itself. Subvert what the ending is going to be… And subvert what the main relationship is that you’re following.

JT: You went from writing Avenue Q and The Book of Mormon to Disney musicals, with Winnie the Pooh and then Frozen. It is a different challenge or set of skills, or does writing the two different kinds of projects feel very similar?

Robert: My projects, they’re all wonderful to me. I put so much of myself into all of them… I don’t draw that distinction. I think we’re always trying to…throw the audience off a little bit. And the line is wherever the line is for the particular tone of the project you’re doing. But I don’t feel like I have two careers. I feel like I have career that’s all about storytelling.

Kristen: I love telling stories with music. Right now, I feel that getting to work with (director) Jennifer Lee, getting to work with (Disney Chief Creative Officer) John Lasseter, I’ve gotten to be in the room and be part of a collaboration with some of the best storytellers of our time. And I’ve learned so much from spending that time. Whether that group of people were in New York City working on a sexy musical, or doing Pixar movies or at Disney, the chance to work with best storytellers is where I’m going to go.

Robert: What’s been one of the main joys of this project, even though it’s been difficult, has been the daily story call that we’ve had with all the Frozen collaborators. We’d get on video conference every day and hash out…what the next story beat was. And then after we’d turn off the box, hopefully write a song.

Kristen: Since fall of 2011, basically we knew, from 12:00pm to 2:00pm, if it was a weekday, we were on our box in our studio in Brooklyn, talking to a boardroom in Burbank.

JT: On Frozen, you two were brought on very early in the story. What were some of the ways the story shaped the songs and vice versa?

Kristen: A good place to start, is…“Let It Go.” Because when we found “Let It Go,” we found our true north for the story… It was the first song that stayed in the movie that we wrote. We had written two or three songs before that. Then we sat in these off-site meetings that are two days of brainstorming with the whole Brain Trust of Disney directors. Everyone was going back-and-forth, “Is Elsa (Idina Menzel) a villain? Is she not a villain? What are they angry at each other for? It’s got to be about a man! No it’s not about a man!” So many questions. And then we wrote, “Let It Go,” and we found this motif.

Robert: This is sort of the motif of Elsa having repressed her power all those years, which was a new development in the story at the time.

Kristen: From that, and that music…we found the type of song that organically grew when we thought about someone that had to leave their whole family and everything they’ve ever known behind and go up alone to the iciest, coldest place in the world in order to let her power truly come out. Once we found that, she couldn’t be a villain anymore.

Robert: It really changed the story. We realized that she had to be likable throughout the story. Not just at the beginning and the end.

Kristen: John Lasseter…they gave him the cd. They showed him the song. We connected via video conference three weeks later. He said, “You guys, if you know how much I’ve listened to this in the car. I only listen to this, over and over and over in the car.” We like to imagine him driving down the highway [singing] “Let It Go!”

JT: So how did the song score develop after “Let It Go” broke the whole thing open for you two?

Robert: We were able to take pieces of “Let It Go” and use them throughout the score… We were able to use that as the modular building blocks of the piece… There’s a part of it in “For the First Time in Forever…” It’s all over “Do You Want to Build a Snowman?” Specifically, in “For the First Time in Forever,” we used that part where she’s referencing her former self, “Don’t let them in. Don’t let them see.” She’s kind of quoting herself in that moment of “Let It Go.”

Kristen: It helped us to find Anna. We knew we wanted her to be funny. But when you’ve had a woman who’s had to be so perfect, who now lives in fear, what is the sister like to this perfect, perfect person, who has had this hidden passion? That sister is probably going to be a little less than perfect. And want connection so badly, if her sister’s been so cold. So it helped us build that relationship in this song.

JT: How early in the process was the film cast? Were you ever writing for specific voices? Or did you ever have to rewrite to fit someone’s vocal range?

Robert: The main parts, especially Idina [Menzel] and Kristen [Bell] were in place. And we knew that we wanted to write a song specifically tailored for both girls. Idina’s got this very beautiful vulnerability in the lower part of her voice. And then she’s got enormous power, iconic power, at the top of her voice. It’s like getting to write for Barbara Streisand.

Kristen: She’s on the list of the five greatest voices alive today… Kristen Bell we saw on one of our first dates. We went to Reefer Madness…back in…2002 or something… She has this purity of sound… If I could work with her every day…I would… You don’t have to [give] any direction. She just knows it.

Robert: She’s funny. And she’s modern. She’s got this voice that sounds like she’s coming from the fifties. This whole idea of subversion, it’s very easy to do with someone like Kristen. She’s got the wit. She’s got the intelligence. She’s got this modern personality with a classic, ingénue voice.

JT: Whether it’s a Broadway show or a Disney musical, when you’re writing the lyrics and melody, to what extent, if any, are you thinking about final orchestration and arrangement? Do you take that on yourselves? Or is that someone else’s job?

Robert: It is someone else’s job. But we have an eye on it, I guess. And we…and [music supervisor] Tom MacDougall and [executive music producer] Chris Montan are the ones guiding the process of the orchestrations. We worked with a number of people, the primary guy was [orchestrator and arranger] Dave Metzger… And [score composer] Christophe Beck… Christophe Beck was amazing. When we do our demos, sometimes we just have piano. And sometimes we add just a little bit more.

Kristen: We worked very closely with Dave Metzger for hours and hours.

Robert: “For the First Time in Forever,” I never thought it was going to be so traditional sounding. I thought, “I’m writing a keyboard song…” But he had violins doing that. And he had brass playing. And all of the sudden we were in this very traditional sounding Disney piece. And it gave the song what it needed to really feel in line with that tradition… That was our first collaboration with Dave. We were so in love with him after that.

JT: In addition to these very classic feeling Disney songs, one of standouts of the film and soundtrack is Josh Gad’s show-stopping song “Summer.” How did you come to write that? Was it written with him in mind?

Robert: We knew Josh would be singing it. I know him really well from The Book of Mormon… We’re all friends. And we call share this sense of humor. Josh is one of the funniest actors that I’ve ever worked with. It just comes out of him. He’s so creative. We also know his voice musically, which is very unusual. He’s got this very, very powerful high voice… He’s got that high vibrato. He reminds me a little of Zero Mostel.

Kristen: We had some miss-hits before. We wrote a crazy song called “Hot Hot Ice.” That had similar lyrics and a similar idea. It was where we found the kernel of an idea of a snowman who’s obsessed with summer, but doesn’t really understand what that means.

Robert: But it didn’t feel innocent. It felt kind of obnoxious, in a weird way. And it was also very Caribbean. Which, nobody wanted to redo The Little Mermaid.

Kristen: I pushed him to go more classic.

Robert: “Let’s write a Christmas song, basically, for this idea.” And so we brought out the sleigh bells. And just slowed down the tempo. And tried to make it really, really [innocent]. And we knew that Josh would get that.

JT: Another highlight of the film and soundtrack is Jonathan Groff’s song “Reindeers Are Better Than People,” which I believe on the soundtrack is exactly fifty-one seconds. It feels like more of a ditty and less of a production number. How did you find that idea, and then decide that was how you were going to execute it?

Robert: We wanted to write something for [Groff’s character] Kristoff… In the beginning we knew that the songs we wrote for the external characters, the secondary characters, were the ones that seemed to be staying. And the ones that we wrote for Anna seemed to keep getting cut as Anna changed and changed and changed. So we wanted to write something for Kristoff. And we wanted to write something for Jonathan Groff. We always assumed we’d write a little bit more. But his character kept denying real songs.

Kristen: In the deluxe version of the soundtrack…there’s something called the “Reindeer Remix,” which was a remix of “Reindeers Are Better Than People.” An expanded version that we wrote, half as a joke, and half as…“Wouldn’t it be fun to put this in the credits? To give Jonathan Groff a chance to do what Jonathan Groff does.

JT: “Let It Go” is the lead-off single from the film and soundtrack, having been rerecorded by Demi Lovato in addition the film’s version sung by Idina Menzel. Were you ever asked to write a song with that in mind? How did that impact the process of writing it?

Robert: No. We were trying to find the movie when we wrote it. I think people reacted well to it… It’s come from the response to the song, rather than from anything we preordained in writing it. We knew we wanted to write a certain type of song for this certain type of character. We would have never that for another kind of character.

Kristen: You’ve got this girl who’s been perfect, perfect, and exalted. And the minute she shows that she’s slightly odd, everybody turns on her and chases her out of the kingdom.

Robert: Just as she’s been afraid of her whole life.

Kristen: And then she has to be all by herself. So there’s this bittersweet thing of leaving everything behind. But also finally getting to let your power out. On the outline, it was labeled…“Elsa’s Badass Song.” I was like, “It’s time to write Elsa’s Badass Song.” It was the dramatic situation that led to that to that kind of song. You couldn’t have her singing something symphonic and classical.

JT: Frozen is obviously a film made for family audiences to see together throughout the holiday season. But cinemas will be offering a lot in that genre this season. Why should families see Frozen, and what do you think it has to offer that’s unique?

Kristen: Holidays can be hard on families. They can bring out…the things that divide us. The way that fear sometimes wins over love. This is about family. And this is about how really owning the love and recognizing the love will always triumph over fear.

Robert: The thing that surprised me most about it, after seeing the whole thing straight through… Was how much there is for different types of people in it… There really is something for everybody. It’s a cliché, but it feels true with this movie. And yet it doesn’t feel like a mixed-bag. It feels like an organic story. And everyone that I’ve talked to who’s seen it so far has had a great time.