ABC News November 21, 2018

The iconic music reborn in sequel 'Mary Poppins Returns'

WATCH: Creating new music for 'Mary Poppins Returns': Part 3

Mary Poppins has provided the soundtrack to so many childhoods for more than five decades. From “A Spoonful of Sugar” and “Supercalifragilisticexpialidocious” to “Chim Chim Cheree,” the only thing as memorable as the magical story of Mary Poppins is the music.

And, just how integral is that music in telling the legendary story of the iconic nanny?

“It wasn't a script that began the development of 'Mary Poppins.' It was music,” Disney expert Jeff Kurtti said. “The connection to that music in the film has a great deal to do with how the story of the film was developed."

Jay Maidment/Disney Pictures
A scene from "Mary Poppins Returns."

Lin-Manuel Miranda, who plays lamplighter Jack in “Mary Poppins Returns” was a big fan of the 1964 film and the music when he was growing up. “Those songs have a hold on us. And then the incredible performances, from those incredible children to Julie Andrew and Dick Van Dyke …it's just across the board wonderful.”

“You just know those songs,” said Emily Blunt, who plays the title character.

(MORE: Emily Blunt felt 'panic and joy' when cast as iconic nanny in 'Mary Poppins Returns')

However, Miranda confessed, there’s one song from the first film that made him so emotional when he watched as a child that he would have to turn off the film.

“’Feed the Birds,’ ... was such a sad song to me growing up that I never saw the end of Mary Poppins until I was in high school [because] I would just turn it off. I would start crying and turn it off at ‘Feed the Birds,’” he said.

The songs of “Mary Poppins” are the product of legendary Disney songwriters Robert B. and Richard M. Sherman, whom Walt Disney referred to as “the boys.”

The songs of “Mary Poppins” are so unforgettable, so what do you do for an encore?

“It's an original musical. I think that's something that was sort of overwhelming at the first, because I thought, ‘Well, here we are. We're writing an original musical for film,’ which I'd never done before, said director Rob Marshall.

(MORE: Dick Van Dyke's first question upon hearing about 'Mary Poppins Returns': Can I be in it?)

When Marshall was searching for songwriters for "Mary Poppins Returns,” he handpicked two of the biggest "Mary Poppins" fans around, award-winning songwriters Marc Shaiman and Scott Wittman.

The pair’s clever and exuberant music powered the hit Broadway musical “Hairspray,” which they followed up with musicals “Catch me if you Can” “Charlie and the Chocolate Factory”.

“I honestly didn't know what I was gonna do if we didn't get [the job]. How do I live the rest of my life if we don't get this movie?” Shaiman said jokingly. “And am I gonna move to a hut on a desert island?”

Wittman said the moment they were told they’d write for the film was “fantastic,” quipping: “But then you have to write it.”

Indeed, the pressure was on.

“You can imagine for us, sitting down to write a new 'Mary Poppins' movie and thinking, like, 'How do we possibly try to compare?'” Shaiman said. “Eventually, you have to stop thinking about that or the fear will incapacitate you.”

Shaiman composed the score and the songs in the film and co-wrote the lyrics with Wittman. They spent months working out musical ideas with the performers, custom-fitting their songs to the actors’ strengths.

Disney
Emily Blunt stars as Mary Poppins in the 2018 film, "Mary Poppins Returns."

“It was like getting the best musical-tailored suit possible,” Miranda said.

“Normally, you really are flying by the seat of your pants when you do a film and there’s no time to prep,” said Blunt, who was filming the blockbuster “Girl on the Train” while working on “Mary Poppins Returns.”

“She would come to us with ragged hair, having played a depressed alcoholic all day,” Shaiman said, “and then she'd be like, 'All right, I gotta be Mary Poppins!'”

(MORE: 'Mary Poppins Returns' star Emily Blunt shares hilarious on-set moment)

In the new movie, Miranda had the honor of singing the movie’s opening number.

“Lin's character welcomes us into the movie and into the time and place,” Shaiman said. “He sings a very, you know, a sweet, gentle melody to welcome you into London.”

“I think we had maybe about 10 different numbers that we tried, because here we are launching into a sequel after 54 years,” Marshall said. “So we really wanted to make sure we started on the right foot.”

Jay Maidment/Disney Pictures
A scene from "Mary Poppins Returns."

In the sequel, Blunt and Miranda also strapped on their dancing shoes.

“Dancing was a new undertaking,” Blunt said. “I think Rob [Marshall] assumed that I could dance. But obviously, he'd never seen my dance, you know. So I think it was a bit of a risk he was taking, you know. But we really drilled those dances.”

Rob Marshall said he knew she would be a good dancer. He said, “I knew that Emily-- has style. I knew that she could sing. I knew she was musical, so I was not surprised that she could dance.”

Miranda said it was trial by fire when it came to the dancing.

“[They said] 'Here’s your hat. Here is your cane. You’re gonna be good at these things,'" Miranda said.

He joked that it was “just after we wrapped” that he was comfortable with the numbers.

Audiences will get their chance to see those dances and hear the songs of “Mary Poppins Returns” on Dec. 19.

Shaiman called the movie, “Our love letter to the original film, the original filmmakers.”

“It’s all in there,” he said. “I think the audiences can rest assured that when they go see ‘Mary Poppins Returns,’ that they're not gonna get cheated out of anything they may wanna hear or wanna see. And then they're gonna get a whole lot of new stuff.”

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