For 60 years, generations of families have had spoonfuls of sugar, dancing penguins and supercalifragilisticexpialidocious delightfully woven into their lives, thanks to Walt Disney's "Mary Poppins."
The 1964 movie, starring Julie Andrews in her feature film debut, sees the titular nanny bring young Jane and Michael Banks, the children of her uptight new employers, on a series of magical adventures to add a little more joy to the family's dynamic.
"It's entertaining on so many levels, and I think adults can enjoy it as much as children," Andrews, 89, told ABC News.
Watch the "20/20" special edition "The Untold Story of Mary Poppins" airing at 9 p.m. Wednesday, Nov. 27, on ABC, and streaming the next day on Disney+ and Hulu.
As Poppins takes her young wards on a journey across early 1900s London, they're joined by Bert, a charming jack of all trades, played by Dick Van Dyke.
"Every minute of that movie was a joy," Van Dyke, 98, told "20/20." Everybody had fun, everybody got along. It was just wonderful. I knew it was going to be a good movie, but it really became a classic."
However, the road to getting the movie made was a long one for Walt Disney. His studio achieved legendary status with the release of the animated classic "Snow White and the Seven Dwarfs" in 1937, but Disney was determined to create a live-action hit.
Disney first became interested in author P.L. Travers' Mary Poppins through his daughters, Diane and Sharon, who were enthralled by the books. The studio made its initial inquiry into the film rights in 1938 and followed up in 1944, but Travers was resistant to many of Disney's ideas for the movie.
"Walt Disney wanted to put animation into Mary Poppins. And Mrs. Travers was not up for that," Becky Cline, director of the Walt Disney Archives, told "20/20." "She thought that it needed to be a much more serious work."
She also demanded the right to approve the script, which the hands-on Disney was resistant to allow. This saga inspired its own movie -- "Saving Mr. Banks" -- in 2013, with Tom Hanks as Disney and Emma Thompson as Travers.
"She was painted as an old dragon. And she could be an old dragon --- and very intimidating, and quite scary at times," Brian Sibley, a writer and friend of Travers, told "20/20." "I always thought there was this conflict within her, in that she was herself quite steely in her manner."
According to Sibley, Travers -- brought up in the Australian outback -- was deeply affected by her father's alcoholism and early death, and her mother's suicide attempt.
"The trauma of her mother's attempted suicide is, I think, a kinda crucial turning point in Travers' life, " Sibley said. "She consoled her sisters by telling them stories about a magic horse."
Travers' Aunt Ellie helped out during this time, with Sibley noting that she was "very much a Mary Poppins character."
Despite being rebuffed by Travers twice, Disney wasn't about to give up on bringing her character to the silver screen. He again inquired about the rights in 1959, and ultimately agreed to pay Travers' $750,000 asking price. She also served as a consultant, got a slice of the movie's profits and the script approval Disney was previously against.
Disney enlisted songwriting siblings Richard and Robert Sherman (who also wrote "It's a Small World" for the 1964 World's Fair) to define the movie's tone. They shifted the time period from 1930s London to the 1910s --- a more colorful era to match the music they had in mind.
The Shermans wrote and presented Disney with early versions of four songs, including "Supercalifragilisticexpialidocious." However, another iconic tune resonated with the studio boss.
"'Feed the Birds' was always a signature tune for Walt, because it spoke to [how] small kindnesses can achieve great things," Sibley said.
This song was also key in winning over Travers, who met the Shermans at story meetings at Disney's Burbank studios. Hours of recorded conversations, much of which was previously unheard, reveal the tension of these meetings as Travers struggled with the reinterpretation of her character.
However, the recordings also reveal that she sang along with "Feed the Birds" --- the same tune that proved key for Disney himself.
"She kinda understood that they were onto something special," Gregg Sherman, Richard's son, told "20/20."
With Travers convinced, Disney needed a leading lady to play Mary Poppins. With some subtle nudging from the Sherman brothers and Disney's secretary Tommie Wilck, Disney saw Julie Andews in a Broadway production of "Camelot." He requested a meeting with her after the show and offered her the role.
"And I said, 'Oh, Mr. Disney, I would --- I'd be thrilled.' I'd never made a movie. And he was so sweet and charming and twinkly and lovely," Andrews told ABC News. "I said, 'But I can't. I'm pregnant.' And he said, 'Oh, that's OK. We'll wait.' He seemed to have this amazing instinct for spotting talent."
Once Travers learned about the casting, she called Andrews shortly after the actress had given birth.
"She said, 'Well, talk to me, I gather you're going to be doing Mary Poppins,'" Andrews recalled. "And I said, 'Well, I've just had a baby and I'm feeling a bit groggy right now, Mrs. Travers.' And she said, 'Well, you're far too pretty, of course, but you've got the nose for it.'"
For Poppins' pal Bert, Disney turned to the popular actor from the comedy series, "The Dick Van Dyke Show."
"When I met Walt, we hit it right off. We both admitted that we just pretended to be grown up and that we were still kids," Van Dyke told "20/20." "I went into his office and he had watercolor paintings of all the scenes from the movie. By the time he got through with that I was just so excited."
Hearing the Sherman Brothers' music was a major moment for Van Dyke.
"Oh, I couldn't believe it, one tune after another. I wept," he said. "It was just the most beautiful thing I ever heard."
Andrews loved the Shermans' work as well, particularly "Supercalifragilisticexpialidocious."
"The songs had a kind of rumpty-tum vaudeville quality to them," she said. "And vaudeville was my background as a kid. So, I grasped that I probably could embrace what Walt was offering."
Despite this, Andrews requested a more upbeat keynote number than the one they had planned for her. Jeff Sherman, Robert's son, provided inspiration when he got the polio vaccine at school.
"My dad said, 'You let somebody give you a shot at school?' And I said 'No, no, dad, they had a little plastic spoon. They put a sugar cube in it. They put the medicine in. And you just ate it," he told "20/20." "My dad looked at me like something was going on, the wheels were turning."
The resulting tune, "A Spoonful of Sugar," gave Andrews the signature song she had been hoping for.
Disney also wanted to lean into the movie's fantastical nature through the use of stop-motion animation, trick photography and revolutionary audio animatronics.
The studio used a technique created by Ub Iwerks, the legendary Disney animator and inventor who was one of Walt's oldest collaborators. This revolutionary new system, called the sodium vapor process, allowed animators to seamlessly combine drawings with the filmed images.
"All of the animation really was shot in front of a giant screen on a sound stage, with none of the characters in the animation in front of us," Andrews said. "So, we had to pretend."
The late Disney animator Frank Thomas, who had worked on animating the dwarves in "Snow White," handled the iconic Dick Van Dyke penguin dance sequence.
“Here’s his feet flying all around and stepping on my penguins. I had them duck and jump and I had them get out of the way any way that they could," Thomas said in a 1984 interview.
Dick Van Dyke recalled seeing the scene for the first time.
"That was such a thrill to me when I finally saw it come together with the penguins," the actor said. " 'Cause I'd done all those moves by myself. It came out so good."
After seeing the finished movie at the August 1964 premiere, Travers still wasn't happy.
"Mrs. Travers made a beeline to Walt and said, 'Well, we need to roll up our sleeves. We have a lotta work to do,'" Walt Disney Archives director Becky Cline told "20/20." "And Walt, I think probably with a twinkle in his eye, said, 'Pamela, the ship has sailed.'"
The movie got rave reviews and generated massive profits for Disney. Andrews' performance earned her a Golden Globe for Best Actress, and it was a major hit at the 1965 Oscars.
"The 13 Academy Award nominations that 'Mary Poppins' received was unparalleled at Disney," Cline said. "Never has before and never has since has one production received 13 nominations at Disney."
It won five Oscars -- Best Actress, Best Special Visual Effects, Best Film Editing, Best Original Score and Best Song (for "Chim Chim Cher-ee"). The soundtrack also spent 14 weeks at No. 1, outselling Elvis and The Beatles that year.
"The critical and personal success of 'Mary Poppins' was so huge for Walt Disney. It put him amongst the pantheon of all of these producers and filmmakers that had for so long thought of him as a cartoonist," Cline said. "And it proved to them that he was indeed a premier filmmaker."
The movie also spawned a musical that opened in London's West End in 2004 (and came to Broadway in 2006), along with a sequel, "Mary Poppins Returns," in 2018.
Walt Disney died in 1966, age 65, and P.L. Travers lived until 1996. She was 96.
Robert Sherman died in 2012, age 86.
"He saw the darkness of the world and just devoted his life to only bringing happiness to people," his son Jeff said.
Richard Sherman lived until May 2024, and died at 95.
"When people find out that my dad was one of the Sherman brothers, they're extraordinarily grateful, and they say, "Thank you. Thank your father for writing the soundtrack of our childhood,'" his son Gregg said.
Before his death, Richard Sherman made one last musical contribution to his Disney family and to the world. To mark the 60th anniversary of "Mary Poppins" and "It's a Small World," he wrote a new verse for the latter.
"And he handed it personally to [Disney CEO] Bob Iger and said, 'I'd like to present this to you as my final contribution to the studio,'" Gregg Sherman said.
That verse, Sherman said, is a prayer for peace.
"Mother Earth unites us in heart and mind / And the love we give makes us human kind / Through our vast wonderous land / When we stand hand in hand / It’s a small world after all."
Disney is the parent company of ABC News.