How did they film the underwater sequences in The Little Mermaid?

In the film, Ariel's sea-creature friends Sebastian, Flounder and Scuttle are rendered as photoreal animations while the underwater scenes make generous use of blue screen technology to create a believable below-the-surface world.

Read on for more information about just how director Rob Marshall and his team created these scenes.

How were the underwater scenes filmed in The Little Mermaid?

The film's underwater scenes were filmed on blue screen soundstages at Pinewood studios in London – with production designer John Myhre designing several sets that represented King Triton’s palace, Ariel’s Grotto and Ursula’s Lair.

Myhre and his team spent countless hours researching and looking at nautical footage, documentaries and images of the colourful underwater world to serve as inspiration, with each area then specifically conceived incorporating subtly different colour palettes and tones.

When it came to filming, a technique called dry-for-wet was utitlised – using state-of-the-art rigs that included wires, seesaws and tuning forks. This meant that the actors were often hooked into a harness with a counterweight on the backside that simulated movement underwater.

Meanwhile, director of photography Dion Beebe created complex lighting effects to simulate the appearance of being under the sea, such that when the water was added in post-production the scenes would look as realistic as possible.

Speaking about the dry-for-wet filming method in the film's press notes, Rob Marshall explained: “How were we going to get Melissa McCarthy to be up there and then down here and then over here, with no floor and no gravity?

“That was one of the first things that John Myhre had to work out, in addition to the design of everything. The practicality of how we were going to do it. The actors were on tuning forks much of the time, which are these big, circular discs that go around the actors.

"They are harnessed in and can spin and move up and down. But everything had to be choreographed very specifically with a large team of stunt men and women, who helped maneuver our characters around.”

Asked what this process looked like from an actor's point of view, McCarthy explained during an exclusive interview with RadioTimes.com: "[There was] a lot of blue! But I think Rob and John being former dancers and performers themselves [helped].

"And just how they built such a safe little world for you to rehearse in and really feel like you're in the space that... so many of the props were real, and we all knew the gist of the visual and I had my 60-foot clamshell there.

"Like, they built a lot of the things – it's not what they look like in the final process, but you could really feel the space. And I think because of how they set us up, they really set us up to succeed!"

Read more

• The Little Mermaid review: Halle Bailey radiates charisma in Disney remake
• How different is The Little Mermaid remake to the original?

How was the Under the Sea musical sequence filmed?

Of course, one of the most iconic parts of the original film is the musical sequence in which Sebastian the crab sings Under the Sea – and so Marshall knew that there was a lot of pressure to get the reimagined version right.

"The challenge of that number was beyond," he explained during an exclusive interview with RadioTimes.com. "I'd never done a musical number like that. I mean, you have one live actor and everything else is created around you. And I really sort of wrestled with how do I crack this?

"Because, you know, in the animated film the sea creatures and the fish are all playing instruments.... it was like a jazz band under the water. [And] I was like this can't be, we're trying to create a somewhat photo-real world down there, where you can really believe that you're there.

"So, what I did was, I remembered that Walt Disney had actually worked with the Ballets Russes when he did Fantasia, the whole Nutcracker suite sequence. And I thought, this is a really good idea because he had a company of dancers that his artists could create from and use as a template. And I thought that's what we'll do!"

Marshall added that he brought the New York-based Alvin Ailey dance company over to London and worked with them, allowing the animation team to study their movement which could then be replicated by the CGI sea creatures.

"It was fantastic, because we had chosen which sea creatures we wanted to work with, but then they could sort of replicate their moves and how they would move and we could choreograph on them, then our artists used them as a template to create this number," he explained. "And we did storyboards and pre-visualisation with it.

"But it was like this massive combination of things to create this musical number out of nothing with one live actor – so it was daunting. It was the one that I said, 'We have to crack this one.' It's a big musical number, and it's the Oscar-winning song. So I'm particularly proud of what we were able to accomplish with that."

The Little Mermaid will arrive in cinemas on Friday 26th May 2023. Check out the best movies on Disney Plus and best shows on Disney Plus, read more of our Film coverage, or visit our TV Guide and Streaming Guide to see what's on tonight.

Try Radio Times magazine today and get 12 issues for only £1 with delivery to your home – subscribe now. For more from the biggest stars in TV, listen to The Radio Times Podcast.