Poldark and Thrones stars boost playwright Dawn King

Iwan Rheon (from Game of Thrones) and Heida Reed (from Poldark) take centre stage in Foxfinder

It's rare that a new name emerges as a West End playwright - and the number of new women writers who find success in commercial theatre is tiny. Dawn King has managed it with her play Foxfinder - and has bagged young stars for the lead roles. But, as she explains, the journey from small fringe venues to London theatre's heartland has been a slog.

Around a decade ago King was staying in a quiet writers' retreat in rural Devon. Like all houses run by the Arvon Foundation it exists to give writers time to think and work.

"It was the middle of winter," King recalls, "and I started to have some strange ideas about the nature I could see around me. So I wrote a journal and from that a monologue for the character who's now William Bloor, the Foxfinder.

Dawn King is dogged in her determination to be successful

"William thinks nature is working against us and that foxes are trying to bring down humanity. But I realised that could make him seem mad and delusional, which didn't interest me. So organically I created a world for him in which everyone shares the same beliefs. And I just went through the first draft asking myself what happens next."

Newly arrived in the West End, Foxfinder's cast is led by Iceland's Heida Reed (known for playing Elizabeth Warleggan in Poldark) and by Iwan Rheon (Ramsay Bolton in Game of Thrones). King, born in Gloucestershire, south west England, deliberately leaves unclear whether the sometimes mysterious action is taking place now or in the past.

The play was first seen in 2011 at the 60-seat Finborough Theatre in west London. King's early career shows how much persistence most young writers need to make any progress.

"I was delighted when I won the Papatango Prize (for new writing) that year, which meant I got the Finborough run. Before that I'd had rehearsed readings and a couple of short plays. But getting something on at a venue which people really respect was a huge step: there were theatre people who'd liked the play but didn't want to produce it. Suddenly they were more interested in what I was doing."

Bryony Hannah (left) plays a neighbour to Heida Reed's character

After that King worked with the BBC Writers Room and five years ago Foxfinder won a National Theatre Foundation Playwright Award. "That was important because it's worth £10,000 - it kept me going. Another nice thing was that the producer Bill Kenwright had optioned Foxfinder soon after the original production. It wasn't a massive amount of money each year but I remember one year thinking I really needed it to come in because I was broke. I've thanked Bill for that."

King also had a play about espionage at the Bush Theatre called Ciphers. But for a decade she kept herself afloat working at the Curzon Soho cinema in London. "I ripped tickets, worked behind the bar - everything."

The life of a married couple (played by Heida Reid and Paul Nicholls (right)) is perturbed by the arrival of Iwan Rheon, the Foxfinder

Another source of income has been productions outside the UK. Foxfinder was first staged overseas in Sweden and then in Australia, Italy, Iceland and Portland, Oregon.

"I've been fascinated by a couple of productions I saw in Germany, which probably has more of a director's theatre than here in the UK. It's wonderful as a writer to feel your play work with audiences even in very different productions and in a foreign language."

But King says she'd started to assume the play would never get a big production on home soil. "And then this spring Bill Kenwright decided to take up the option. But that depends on so many things aligning. For a start you need a suitable venue - and the right director in Rachel O'Riordan.

"It's at least two years since Iwan Rheon said he was interested in playing William. Once you've got a big building block like that, other things start to click.

"And I was very keen we should run the play in the autumn because that's when it's set and you need the sense of winter approaching. There are some factors at play which are probably less obvious to the public."

Does King think being a woman has been a hindrance to making it in the tough world of commercial theatre?

Iwan Rheon (left) and Paul Nicholls (of EastEnders fame) go on the hunt for the animals believed to be causing the country's demise

"There have been some recent statistics about the number of productions in Britain of new work by female playwrights. The figures are shockingly low. I know I've been quite lucky and I'm especially lucky to have worked with great female directors like Rachel. I won't pretend there isn't a more general problem for women - but it can be a hard profession for anyone."

"I'd be delighted to have a commercial hit in the West End. I'd also be delighted to find it helps open doors in subsidised theatres. But if I look back at this first part of my career I'd have to say there isn't always much logic apparent. Sometimes something great happens and then it can take a really long time for the ripples to ripple out. You fear nothing is happening but you just can't give up."

For now, King's career is moving closer to the big and small screens. She's busy on a screenplay of Foxfinder and on a virtual reality project. "But with TV I always seem to come nearly nearly nearly but not quite - but I hope Foxfinder might help me there. I'm also looking for my theatre project for next year. But mainly I'm just enjoying what's happening here and now."

Foxfinder is playing at the Ambassadors Theatre in London.

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