Mary Poppins Returns has an amazing animated sequence at its heart, one that looks poised to be a highlight of the film. If you've seen the latest trailer for Rob Marshall's incredibly belated sequel to Disney's 1964 classic, then you've seen glimpses of what is dubbed the "Royal Doulton" sequence. Here's what we learned about it on set.

It wouldn't be a Mary Poppins film without some animated/live-action crossover. "Supercalifragilisticexpialidocious" from the original is a beloved highlight, making Walt Disney's adaptation of P.L. Travers' books stand out from both their source and the myriad of other Hollywood musicals at the time. This style has been returned too in various forms by Disney over the years - the alt-reality of Who Framed Roger Rabbit and the reverse, animation-coming-over-to-the-real-world premise of Enchanted - and so was a natural fit for Mary Poppins Returns.

Related: Mary Poppins Returns Teaser Trailer Breakdown

When Screen Rant visited the set of Mary Poppins 2, we got up close with the sequence, learning how it fits into the movie and some secrets of its making. The whole thing kicks off when the new generation of Banks children break a 19th-century whirling bowl (made by Royal Doulton China, giving the sequence its name), with their new nanny Mary Poppins (Emily Blunt) finding a rather innovative way to fix it: she spins them (along with Lin-Manuel Miranda's Jackinto the bowl.

Inside, they learn that the family heirloom has more secrets than they realized. The humans drawn on the surface are in fact anthropomorphized animals living in an idyllic London park. These creatures are, of course, the classic Disney design with a Poppins twist: a ferret with a bowler hat, a polar bear in a tuxedo, an owl in a suit, a cow in a dress, a bulldog concierge.

All of that, though, is build up to the animated musical number setpiece. Per production designer John Myhre, "Mary Poppins picks up her umbrella, and she holds it over her head and she starts spinning it and the three-foot umbrella grows into a thousand-foot tent". What happens next is a big song and dance set piece involving Mary and Jack delivered to the animal audience.

Mary Poppins Returns Animated Sequence Emily Blunt and Lin-Manuel Miranda

While the idea of an animated musical beat obviously comes from the DNA of the original film, this isn't just a retread. "What made it, distinguished it, in its day was that there was an interaction between live action characters and animation," producer Marc Platt said of the first movie, before adding, "which we do as well. We do it in our own contemporary way."

This can be seen in the incredible attention to detail. Firstly, the bowl isn't just a plot device but worked into the animation style and geography of the world. As Myhre explained, old china develops cracks, something Rob Marshall wanted to work into the movie: "I guess as its fired there are these little cracks. And I guess as you wash it, it gets dirty. So Rob said, 'well if they’re going into the world of the bowl, I want to see the crazing.'" You can actually see this effect in the trailer shot of the group in the carriage, although what you may not be able to make out is that the world is "in this curved dimensional bowl shape. That’s also something they use in the storytelling. It’s not just flat. They can slide down or up."

Mary Poppins Returns Royal Doulton Animated Sequence

The sequence may also boast the film's most genius production decision. Costume designer Sandy Powell felt that, in the original, "the animation is a bit removed from the actors", and to better blur the lines between live-action and cartoon found a low-tech solution: "wouldn’t it be interesting to make the people look like their clothes had been drawn by the animators?" As Powell explained, the final results were simple yet intricate:

"Mostly it’s cottons and canvas and a plain white background to see how paint would take and then making clothes and painting on them to look like cartoon drawings. I got in touch with the animators at the beginning because I wanted to see examples of how they were going to paint the style of the animation, the style of the drawing, which you can see is a very old-fashioned line outlines and watercolors. I wanted the effect on all of these costumes to look like watercolor on paper with the white coming through."

We saw a short clip of the sequence, and now from the trailer it's in a more complete form, you can really see how it works.

How the full Royal Doulton bowl sequence ends up in Mary Poppins Returns we'll have to wait until December to see, but from all the effort that's gone into it, it's definitely what we're most excited for.

Next: Mary Poppins Returns Trailer & Poster: Mary is Back to Save the Day

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