Sharon Rooney on playing a mermaid in Tim Burton’s Dumbo: “It was overwhelming”

Sharon Rooney as Miss Atlantis (far left) with the cast of Tim Burton's Dumbo PIC: Disney

It’s all Ella Mint’s fault. When Sharon Rooney was three, maybe four years old, she was taken to her first pantomime at the King’s Theatre in Glasgow. She’s pretty sure it was Cinderella. It might even have starred Elaine C Smith (an actor she’s since worked with on the sitcom Two Doors Down). What’s important, though, is that when the show started, little Sharon was so swept up in the spirit of it, she got up on her chair and started dancing. That’s when an old lady leaned over to her Gran and said: “Look at her, she’s in her element.”

“I thought she said: ‘She’s Ella Mint,’” beams Rooney. “And that was the moment something went click. I became Ella Mint. I’d say to my Gran, ‘Ella Mint is coming. She’s doing a show. One night only!’ And my Gran would go, ‘Brilliant… Yey!’” She mimics the resigned enthusiasm of a relative forced to indulge a child’s umpteenth living room performance. “But she would say to me, ‘You’re going to be an actress one day.’ And I would say, ‘No, I’m going to be Ella Mint. I thought being ‘Ella Mint’ was being an actor and an entertainer. My mum will still write on cards: ‘Good luck, Ella!’

“I’m glad I went to that panto,” she adds, with a laugh.

And so she should be. Thanks to that panto and the subsequent childhood alter ego it inspired, she’s now sitting in a hotel room in London, literally pinching herself at the fact that the movie she’s here to promote – her debut movie no less – is Tim Burton’s new live-action version of Disney’s 1941 animated classic, Dumbo, a film co-starring Colin Farrell, Michael Keaton, Danny De Vito and a flying CGI baby elephant with over-sized ears.

Rooney plays Miss Atlantis, one of the supporting troupe of misfit circus performers whose fortunes look like they might be about to change when Dumbo’s special talent is discovered. Hitherto best known for her TV work – especially her breakthrough role as the acerbic-yet-vulnerable teenager reckoning with mental health issues in the critically acclaimed comedy drama My Mad Fat Diary – Rooney still can’t quite believe she’s playing a mermaid in a Disney film directed by Tim Burton (another childhood hero).

“The last thing I did was go and meet with Tim,” she says of the audition process. “And that felt like, ‘Does it get better than that?’ And then when it was a ‘Yes’…” She trails off. “It still feels a bit like, ‘Are you sure? Are you sure?’”

She watched the film for the first time the previous evening and confesses she had to put on an emergency eye-mask this morning because her eyes were so puffy from crying.

“I know it sounds sugary-sweet, but it was overwhelming,” she says when I ask what it was like walking on set for the first time. “It smelled like a fairground. Honestly it was like…” She pinches her arm again. “And being the mermaid… the dress that you get to wear… I’m just a girl from Glasgow. How do you get there?”

Rooney grew up in the West End, not far from the city centre (she’s too much of a homebird to leave Glasgow and currently lives just on the outskirts). She says her childhood was a normal one, filled with multiple viewings of Disney movies on video, sometimes wearing out the VHS tapes, watching and rewinding, watching and rewinding, until they had to be replaced.

Dumbo was a particular favourite, in large part because she loved the song Baby Mine, which Dumbo’s mother sings to her outcast baby as she rocks him in her trunk. Rooney used to sing it with her Gran. “It meant a lot to me and her,” she says.

For the new film, Arcade Fire have recorded a cover version that plays over the end credits, but in the actual film Burton has Rooney sing it, accompanying herself with a ukulele, which she had to learn. It must have been quite a moment when she realised she was going to have to perform such a show-stopper?

“I feel physically sick even talking about it because it’s a huge responsibility. I haven’t told anyone. Only my mum and dad know that I sang it. It feels too good to be true. And it’s terrifying. Everybody I’ve met has said: ‘Oh, is the song still in it? It’s my favourite bit.’ And I’m like: ‘Eaaagh!’”

For all Rooney’s endearing modesty, she knows she’s worked hard to get here. She’s been through the countless auditions, the almost getting things and the outright rejections. Straight out of college she spent three years touring the country doing theatre education and was on the verge of packing it all in to retrain as a nurse when her agent sent her the script for My Mad Fat Diary. She knew within half a page she was perfect for the role. “I thought, ‘OK, if I don’t get this, then that’s it. And if I do get it, well, I’ll worry about it later.”

That fearlessness, that willingness to jump right in at the deep end, has stood her in good stead. My Mad Fat Diary was her first TV gig and she played the lead. Her first theatre role was in Phyllida Llloyd’s all-female Henry IV at the Donmar Warehouse. And now there’s her big screen debut in Dumbo, for which she’ll walk the red carpet in a few hours time, taking her parents, who are on the train down from Glasgow as we speak. “They’re buzzing,” she says. “I’m a nervous wreck. I feel like a duck.” She mimicks a duck’s frantic paddling beneath its surface calmness.

But if there’s one thing she’s sad about, it’s that her gran isn’t alive to see her sing Baby Mine on screen. Still, she probably wouldn’t have been surprised at where young Ella Mint has ended up.

“She used to tell me, ‘Don’t worry, you always end up where you’re meant to be,’ says Rooney. “So, thanks Gran!”