Aardman Productions, the Oscar-winning British studio behind Wallace & Gromit and Shaun the Sheep, is breaking its longstanding relationship with the BBC and turning to Netflix for its first animated musical, the Guardian can reveal.

An official announcement will be made on Friday that Aardman is shooting Robin Robin, a family film about a baby robin redbreast that goes missing. A cast of woodland creatures will be made from natural materials, such as woollen felt and twigs.

The film’s message was about “being yourself”, Aardman’s managing director, Sean Clarke, told the Guardian . “It’s a bit like The Ugly Duckling meets Oliver Twist. An egg fortuitously rolls into a rubbish dump. The robin hatches and is raised by a family of mice. The robin grows up trying to act like a mouse. She fluffs her feathers to look like a mouse and enjoys the delights of cheese – but she can’t sneak into houses.”

Behind the scenes at Aardman, making the animated musical Robin Robin. Photograph: Chris Lyons/Aardman

Aardman was founded by Peter Lord and David Sproxton on a kitchen table in Bristol more than 40 years ago. They discovered Nick Park in 1986 while he was still a student and went on to collaborate on the first of their Wallace & Gromit hits, A Grand Day Out. The studio now has up to 300 animators and technicians in Bristol, and more than 100 awards, including four Oscars.

Clarke described the musical as “incredibly exciting”, adding: “We’re taking all those skills of storytelling, puppetry and art, and turning it into a new look. It will still have the Aardman hallmarks of humour – humour that the adults will get, and more slapstick for children. It feels like it could have been a much-loved book that’s been passed from generation to generation.”

The directors, Daniel Ojari and Mikey Please, have written the screenplay with Sam Morrison.

Ojari said of the story: “A big part of it is celebrating difference and the thing that makes you you.”

Please added: “We establish a world in which woodland creatures stick to their own and difference is something to be wary of. Robin learns that the thing that makes her different is actually a benefit for her and for others. The music plays with that idea; when varying tones overlay each other, they harmonise into something more beautiful.”

The woodland creatures would be “rough around the edges”, the film-makers said, “with the mice family being burglars – but morally good burglars who only take what they need”.

Sarah Cox, Aardman’s executive creative director, said the multimillion-pound production would be a 30-minute mini movie “full of captivating tunes, classic with a modern sensibility”.

“There’s something about animation and music that has such a guttural impact on you when you see things syncing in time to music. Aardman hasn’t really embraced that yet.”

A puppet-maker testing different material for the prototype bodies of a mouse puppet. Photograph: Chris Lyons/Aardman

The film would be stop-motion animation, she explained: “We’re trying to get a crafted, handmade look in a very professional way. Robin will have an armature and a resin core body, covered with felt. The look is quite different from previous Aardman characters. They won’t be made from Plasticine. But it will feel reassuringly Aardman in its sensibility and its character-driven comedy.”

They were drawing up a “dream” cast for the voices and planned to shoot in the new year, releasing the film next Christmas. Work had begun on the props and art direction at the Bristol studio. Cox said: “I just saw a tiny mouse animation. I was almost weeping with excitement.”

Clarke acknowledged that Aardman had become synonymous with the BBC. Asked why the musical was being made as a Netflix original, he said they would work with the BBC again, “but Netflix has the ability to buy for the whole world rather than just the UK. Everything we’ve done with Shaun the Sheep and Wallace & Gromit has been done with the BBC, but BBC budgets are under pressure. The last one we did was probably four or five years ago. The BBC would have loved to have taken Robin Robin. But they weren’t in a position to afford it.”

Both Aardman and Netflix said they hoped this would be the first of many collaborations.

Clarke said: “They are a good partner … They respect a film-maker’s vision.” While Alexi Wheeler, Netflix’s head of kids and family originals, said the project was part of ambitious international plans for animated productions, recognising that children worldwide want great storytelling. “For so many generations, the great kids’ content came from one country, the US. We’re seeing great new stories coming from right across the world.”

He said of Robin Robin: “It was a love-at-first sight project … It was so heartfelt.”