Oscar-winning costume designer Sandy Powell even helped dress the cartoon animals for a song and dance number.

"It was the first movie I saw — a long time ago," says "Mary Poppins Returns" costume designer Sandy Powell, about the original 1964 classic children's film starring Julie Andrews in the titular role. "I do remember Mary Poppins's dress, and that's always stayed with me. Also, the fact that, you realize now, you know all the words to the songs still."

It's all come full circle as the three-time Oscar-winner (and nine-time — so far — nominee) excitedly took on the momentous job of bringing everyone's favorite flying nanny, the Banks siblings and co. forward two decades via costume. Grown-up Jane (Emily Mortimer) and Michael (Ben Whishaw) are raising the latter's three children after his wife's death a year ago. Money management hasn't ever been his thing, either, so the family home is in jeopardy of repossession. Yeah, dark. Hence the urgent need for a visit from Mary (Golden Globe and SAG Award nominee Emily Blunt), who hasn't aged at all, as Michael incredulously comments (only to be met with a scolding from his former nanny). But she has received an ultra-chic — but authentic to the original character — outfit update from Powell. 

Mary Poppins (Emily Blunt). Photo: Jay Maidment/Courtesy of Disney Enterprises

Mary Poppins (Emily Blunt). Photo: Jay Maidment/Courtesy of Disney Enterprises

"Her silhouette is ingrained on everyone's memory, isn't it? We know it. It's an iconic image and I knew I had to reference that, but didn't want it the same. We didn't want to put Mary Poppins in 1934 in something that would have been worn in 1910," explains Powell, who also designed another awards season, erm, favorite, "The Favourite." But in a moment of sartorial kismet, 1930s fashion actually nods back to Edwardian style, with mid-calf hemlines and nipped-waist silhouettes.

"I designed a 1930s version of the belle-tiered, elegant longline coat, with the edition of a double-cape at shoulders," adds the costume designer. "Just to make it more modern and fashionable for the 1930s and also to create a bit of movement." (Also perfect for a jaw-dropping landing via aeronautic umbrella.) In a nod to the traditional nanny's uniforms in navy, Powell stayed within the blue family for Mary's iconic coat. But she "bumped up" the shade to a brilliant cobalt to stand out in the more dimly-lit interiors of the Banks household.

Georgie (Joel Dawson), Mary, Anabel (Pixie Davies) and John (Nathanael Saleh). Photo Jay Maidment/Courtesy of Disney

Georgie (Joel Dawson), Mary, Anabel (Pixie Davies) and John (Nathanael Saleh). Photo Jay Maidment/Courtesy of Disney

Powell also integrated cheerful geometric prints and textures — authentic to post-Art Deco, 1930s fashion — that just jump off the screen: hypnotizing chevron weaves on Mary's jackets and skirts, whimsical polka dots on her bow-tie and gloves and delightful orange contrasting stripes on shirting. "I didn't think she was remotely floral," laughs the costume designer. "There's something nice about graphic images and shapes that appeal to children. I didn't want it to be remotely messy; I wanted it to be clean-cut and clear." Also, look closely to catch the diagonally-shaped buttons that Powell and her team also specially created for the jackets.

True to her legendary M.O., Mary also takes Michael's children Georgie (Joel Dawson), Anabel (Pixie Davies) and John (Nathanael Saleh) on fantastical journeys via everyday household items, like the bathtub. Obviously, they need appropriately magical outfits. For a dive into the evening bath-turned-nautical journey, the kids and Mary change into brighter, beach-y hued and Edwardian-inspired swimwear based off their usual stripes and polka dots prints. "Mary Poppins is wearing blue, a much brighter blue than she would have worn normally in real life, and with the exaggerated chevrons; her hat has a flying fish on it, instead of a bird, on her daytime hat," says Powell.

Mary, Georgie (Joel Dawson), Anabel (Pixie Davies), Jack (Lin-Manuel Miranda) and John (Nathanael Saleh). Photo Courtesy of Disney

Mary, Georgie (Joel Dawson), Anabel (Pixie Davies), Jack (Lin-Manuel Miranda) and John (Nathanael Saleh). Photo Courtesy of Disney

The four — along with singing, dancing and rapping lamplighter Jack, played by (Emmy-, Grammy-, Tony- and Pulitzer-winning Lin-Manuel Miranda of "Hamilton" fame) — also jump into a 19th-century art-covered Royal Doulton bowl to join an animated song and dance sequence — in the vein of the beloved "Supercalifragilisticexpialidocious." To help make the live-action actors blend in seamlessly with the animation, Powell pitched an ingenious idea: "Why don't we try painting the costumes to look as if they've been painted by the animators?" 

Of course, the answer was a "yes." Powell and her painting team went through a painstaking "trial-and-error" process of different painting techniques on cotton and canvas. The final result: Museum-worthy, "watercolor-y" 2D-painted bows, ruffles, pleats and buttons decorate the 19th-century silhouettes, which fit into the era of the artwork on the bowl. Mary and Jack also change into pink-and-purple striped and polka-dotted stage looks for a spectacular song and dance number, backed by similarly clad cartoon circus and farm animals. And, yes, Powell kind of designed the animated outfits, too.

Mary and Jack with their backup talent. Photo: Courtesy of Disney

Mary and Jack with their backup talent. Photo: Courtesy of Disney

"The costumes that [the actors] are wearing came first and then the animators started building their world. They would pop images of my costumes in to see how it would all work together," she explains. Powell also sent the animation artists reference images for 1800s clothing, so they could draw matching outfits for the pig, elephant, hippo and all. "They would send me little sketches of the animals in their ideas of costumes and then I'd do adjustments," continues Powell. "'I think it would look a bit better if it was like this.' Then we went back and forth for a little bit." Because the dancing animation worked best with straightforward patterns, the stripes and dots consistently carried over into the cartoon world, but in heightened, exuberant colors. 

Along with costume designing the cartoon extras, Powell influenced the ultimate look of Meryl Streep's eclectic artist and restorer character, Topsy, who's dressed in deco prints and Boho fringe, and accessorized with paint brushes and pencils. The costume designer's inspiration ranged from the flapper-style of 1920s actress Louise Brooks to the eccentric, turban-sporting Edith Sitwell to heiress Nancy Cunard and her signature stacks of Bakelite bracelets up each arm. But when the two Oscar winners met for their first fitting, Streep suggested a slight tweak, inspired by Powell herself.

Topsy (Meryl Streep) chats with Mary and the kids. Photo: Jay Maidment/Courtesy of Disney

Topsy (Meryl Streep) chats with Mary and the kids. Photo: Jay Maidment/Courtesy of Disney

"I really wanted Topsy to have a turban and not see her hair — just have the turban and big jewelry," says Powell. "And then Meryl came into the room and said she would like a bit of hair. 'But I want it that color,' she said, and pointed at my hair," laughs Powell, about the origins of Topsy's bright-red tousled bob. 

As for the Banks family, Jane carries on her suffragette mother's legacy as a workers union organizer in beautiful high-waisted wool trousers, tweedy plaids and a collection of berets (that I need). "I wanted her to be an emancipated woman, and, of course, the really iconic way of doing that is to put her in trousers, so she could be active," explains Powell. "She's always running somewhere, rushing around, and she couldn't be doing that in a skirt and heels. I wanted her to be free to move and be strong."

Michael struggles with raising the kids without his wife and working a soul-less office job. "He's in a cozy, artistic dad look. At home, he's a little bit disheveled, a little bit worn-out," says Powell, about his forest-green, chevron-weave cardigan. "Then he wears the suit to work, which I feel he's never that comfortable in, because he doesn't really want to be working at a bank anyway. By the end, when everything is made good, he's looking dapper and handsome in the boater and the blazer."

Jane (Emily Mortimer), Michael (Ben Whishaw), Georgie, John and Mary. Photo: Jay Maidment/Courtesy of Disney Enterprises

Jane (Emily Mortimer), Michael (Ben Whishaw), Georgie, John and Mary. Photo: Jay Maidment/Courtesy of Disney Enterprises

The Banks kids are, of course, adorable in their pocket-size pea coats, Fair Isle knits, mini-hats and little high-waisted herringbone shorts. "It's quite difficult to get kids of today to wear knitted things made of real wool because everybody is used to very, very soft things, and synthetics are all comfortable and stretchy," she says. "But they were all very professional kids." Powell also intentionally made their clothes "a bit small" to depict a year's worth of rapid growth and a distracted dad not picking up new clothes for them. "I didn't want them to look too perfect," she says, which, in itself — and with her design acumen — incredibly perfect.

"It's very exciting," says Powell, about designing for the beloved characters in the first film she ever saw. "There was no question of a doubt when I was offered the job that I was going to say no. I was absolutely, 'Yes, I want to do this. It's important."

Follow Sandy Powell on Instagram at @thesandypowell. "Mary Poppins Returns" opens in theaters on Wednesday, Dec. 19.

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