MARY Lennox, the heroine of The Secret Garden, the classic children’s novel by Frances Hodgson Burnett, is described as "Mary, Mary, quite contrary," and as "a self-absorbed child who gave her entire thought to herself," writes DAVID WARD.

That’s bad enough; but someone else piles on the contempt, calling her "a tyrannical and selfish little pig."

Yet Natasha Cottriall loves Mary; which is good news, because she plays Mary in Jessica Swale’s stage version of the story, which is running at Keswick's Theatre by the Lake until January 13.

Natasha admits that, like Mary, she might have sometimes been a stroppy 10-year-old. “But I think I was a little bit sweeter than her because I had so much more attention than she did – I was an only child.”

Natasha’s tricky job is to bring to life on stage this little girl who lives in India but, after her parents die in a cholera epidemic, is sent to England to stay with an uncle she does not know. She is gradually transformed from grouchiness to joy by the adults and children she meets and by the walled garden she discovers. It’s a touching and powerful story that has gripped readers young and old since it was first published more than a century ago.

“There is so much in the story – darkness, sadness, light; everything in life is there,” said Natasha. “When the audition came up, I knew I really wanted the part because I love the story so much. As a child, I used to watch the film starring Maggie Smith at least once or twice a week. I pretended to be Mary. And Mary is my middle name.”

As we spoke, Natasha was re-reading the novel and preparing herself for a role that will see her almost permanently on the Main House stage during performances lasting two hours or so. “It feels like a really good challenge. I’ve never had a part where I have had to do so much and be the focus of the action. It’s a bit scary.”

Natasha grew up in Wigan, started dancing lessons at three and first appeared on stage as a parrot. She later joined a local drama group, played an extra in Hollyoaks and at secondary school appeared in Grease, a show that developed her interest in musical theatre and prompted her to take singing lessons.

“I’d already decided by then that I was going to be an actor, no matter what. It was just the idea of being able to create lots of different parts that appealed. Even now, when I do another job between acting roles, it’s as if I’m playing the part of someone else doing the job.”

Not that there have been many gaps between parts in the three years since she graduated from Mountview Academy of Theatre Arts, which she loved.

Her career biography is one of the shortest and most modest ever to appear in a Theatre by the Lake programme but still reveals how busy she has been.

Natasha played Rosie Griffiths in Doctors, the BBC soap set in a medical centre, acted with Rob Brydon at the Old Vic in London and was Little Red Riding Hood in Stephen Sondheim’s musical Into the Woods at the Royal Exchange in Manchester.

Before starting work on the Secret Garden, Natasha spent ten months in the West End in Beautiful: The Carole King Musical. “I had the most brilliant time. When you are at drama school, you go to a West End show and wonder whether you could imagine yourself up there, on stage. And then you are on that stage and think, ‘This is my life’. It’s crazy - but sometimes it actually happens.”

The cast of 11 actors plus puppet robin, fox, mouse, squirrel and dog, are in Keswick for a ten-week stay and 71 performances of The Secret Garden, including school shows that start at the most unactorly hour of 10am.

Natasha knows the South Lakes well from family holidays around Windermere (“I always wanted to go to the Beatrix Potter museum”) but is now in Keswick for the first time. “I’m so excited to be here, especially at Christmas. It’s amazing to be in such beautiful surroundings.”

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