It took Georgina Duncan a few seconds to realise that Indhu Rubasingham, when announcing the winner of the Women’s prize for playwriting last week, was talking about her drama, Sapling. The 30-year-old recalls the moment: “The first sentence I heard her say, I was like, ‘That could be any of the plays.’ Then I was like, ‘Holy shit! This is the maddest thing that’s ever happened to me.’”

The news still hasn’t fully sunk in, but anyone who has read Sapling will not be surprised by Duncan’s victory. Set in Belfast in the 1990s, the play follows 16-year-old Gerry, whose older brother Connor was murdered 10 years earlier by another child. “Someone described it as being about the scar tissue behind grief, which I thought was so eloquent,” Duncan says. The play was born out of her own fear of loss: “Grief is something we all experience in our lives. And it frightens me.”

Duncan admits she didn’t know much about the Troubles before she began writing Sapling but , determined to make the play “right”, she took prison tours in Belfast, and rode in the back of a black cab with a driver named Cedric to absorb the city’s history and geography, while also meeting Northern Irish actors to talk through her ideas. “I paid them with a pint and a bowl of chips.”

Her dedication paid off: Sapling rigorously paints a detailed picture of a scarred community. Even just on the page, there is an aliveness to her words, and she writes the kind of characters actors will be eager to play. This makes sense as Duncan is a trained actor, too. She graduated from the London Academy of Music and Dramatic Art in 2018 and went on to star in The Mousetrap, the Agatha Christie West End staple and world’s longest-running play. Her time performing, she says, informs every piece of her writing: “When I write, I do speak my play aloud like a madman. Because I’ve said words in front of a live audience, I know what that feels like.”

Storytelling, it becomes clear, runs through Duncan’s veins. She speaks fondly of her childhood in Lancashire, where she’d dance around her living room to Riverdance or watch Kate Bush videos on repeat. “Her music videos are theatre,” she says. “I’d watch them on loop.” Although her mother and father had no background in the arts, they encouraged her to follow her dreams. “I had working-class parents, they’re not from this world at all. We were quite skint, but they did everything they could to help me.”

Applying for drama school became Duncan’s obsession as a teen. “I totally had the blinkers on,” she says. Writing came later, in the years after she graduated, when she had quit acting for a while. “I remember ringing my mum and saying, ‘I think I want to write.’ And she said, ‘Well, just do it.’”

Duncan joined Soho theatre’s Writers’ Lab, where the origins of Sapling were formed. “I wrote most of the play on my phone on my commute,” she says. “I’ve stayed on tubes way longer than I should have because I got into a flow state.” In the years since, she wrote another play (“still in a drawer”) and a one-woman show called Asbo Bozo, about a social worker in Wigan. She performed it in London last year: “People seemed to be very moved.”

Still, it has taken Duncan a long time to feel successful. Sapling was “shopped around”, with several versions of the script being entered for lots of prizes. “It got close a couple of times,” she says. “It was like the nearly man. The industry is so tough for people starting out, especially for people emerging with no context or anyone in the industry to open doors.”

Which is why Duncan thinks awards like the Women’s prize – which was founded by producer and writer Ellie Keel, alongside Katie Posner and Charlotte Bennett of touring company Paines Plough – are so important. “Prizes are one of the few things we’ve got that are sort of a level playing field,” Duncan says. Keel, frustrated by the lack of plays by women produced on national stages, pitched a prize for female playwrights in 2019. It certainly feels essential: in its 50-year history, the Olivier award for best new play has only been won by a woman seven times.

For Duncan, this feels like the start of something. With the £20,000 prize to support her, she hopes to be able to dedicate time to “really understand how” she writes. “It is the greatest gift. This prize has completely changed my life.” Now, for the first time, Duncan feels confident enough to call herself a playwright. “I feel,” she says, “like I’ve been legitimised.”