Like millions of viewers, actress Sharon Small has been addicted to the BBC1 drama Happy Valley, which concluded this week.

The Scottish mum-of-two praises writer Sally Wainwright, who was also behind Scott and Bailey, Last Tango in Halifax and Unforgiven, for her characterisation of the programme’s main character, Sgt Catherine Cawood.

“There are lots of strong roles for women in their 30s. My beef is that it tails off in your forties,” the 47-year-old explains.

“I’ve been watching Sarah Lancashire in Happy Valley. It’s really, really good. Sally Wainwright is one of the few writers to be writing strong women over 40.”

Making her RSC debut as Alice Arden, a sexy, adulteress plotting to kill her husband, is something Sharon says was “really exciting”.

Polly Findlay’s modern production of Arden of Faversham, a true Elizabethan crime of passion, also stars Keir Charles as her lover Mosby and Ian Redford as her husband Arden.

“The first time we came to rehearse at The Swan I thought, ‘I’m going to be on this stage’ and that’s when the magic began,” says Sharon.

“Alice is a woman led by her heart and her passion. The pairing of some people is toxic.

“I thought she didn’t have to be Machiavellian, but a woman who had the idea to kill her husband and had to improvise when everything went wrong.”

Some critics have questioned the decision to update the anonymously written 1591 play to modern Britain but Sharon feels it serves to highlight the play’s relevance.

“This is a woman from the 16th century but what it shows you is that these stories of love, passion and adultery still exist today.

“People have flaws – the assassins are very flawed and not particularly good.

“We have an historian, who is on hand for the RSC. He was fantastic and gave us lots of information on the crime. I read the account in Raphael Holinshed’s Chronicles on which the play is based and a transcript Alice had written about how she felt about Mosby.

“But I did ask the question, ‘Why don’t I just divorce Arden?’ We’ve created a world where this is not an option.”

Sharon says director Polly created a rehearsal space “where anything goes, no matter what”.

“I did think I was going to be in this 16th century costume drama – but it went into Coen Brothers and Breaking Bad territory.

“The whole play is about a terrible crime. The one aim is to kill Arden. When Alice sees his body in the snow at the end it’s like ‘oh my God, what have I done?’”

On stage as the sexually provocative, manipulative yet frightened Alice, Sharon wears a tight-fitted skirt and spiky high heels.

“I chose the shoes myself,” she reveals.

“The ones I was originally going to wear weren’t high enough. They didn’t seem to have a sense of sex. So I went out and bought a pair of Aldo heels in London. I just thought this is a woman who has to have ‘bleep me’ shoes.

“What’s lovely is there’s been a real mixed range of ages in the audience and young people are really enjoying it.

“It has good shock value – but if you sit in the front row do not wear anything you value, as you may get covered in blood.”

Arden of Faversham is part of The Roaring Girls season of Jacobean plays in the Swan Theatre centred around strong female characters. It also includes The Roaring Girl, The White Devil and The Witch of Edmonton.

As an actress Sharon would like to see more new writing focussed on “tenacious” women.

“The thing is we cannot change the old plays which were written for older men and boys. The classics are still going to be produced. What we can do is look at new writers. Often they create women so strong they are either more masculine in their behaviour, or crazy. You often find it’s women rather unravelling than stepping up,” she says.

“I’d like to see new work where you see women and their tenacity, stamina and sheer strength. Women are great diplomats and have incredible stamina. It’s the mother who gets up in the night to look after her baby – women cannot switch off. Those are the kind of women I want to watch.

“In Men Should Weep at the National I played a woman holding it together in a 1930s Glasgow slum while her husband was out of work. I would like to see more of those courageous women.”

Sharon is best known as Trudi Molloy in BBC1’s Mistresses about four female friends. Trudi finds out her husband had not been killed in 9/11 but was a fraudster.

“I do not know of any other British TV dramas showing the lives of four women in their 30s and 40s,” she says. “Women with all their flaws.

‘‘As four actresses we tried hard to keep it as real and authentic as we could. Within the confines and we did genuinely become good friends in a very supportive way.

“Orla (Brady) is living in LA and Sarah (Parish) lives out of London but we met up at Christmas and had a lovely Champagne brunch. It’s rare we can get all of us together.”

Sharon’s first major TV role was playing police detective Barbara Havers in Inspector Lynley Mysteries, and her co-star Nathanial Parker recently played Henry VIII in Wolf Hall and Bringing Up The Bodies at the RSC.

Sharon grew up on the east coast of Fife but moved to London when she was 19 to go to Mountview drama school – and she has never left. She now lives near Muswell Hill with her partner Dan Bridge, a freelance photographer, who gave up his job to look after their two sons Leo, aged seven, and five-year-old Zac.

“All my family are up in Scotland still. I miss them a lot, especially my mum.”

She also misses her children when she is working away.

“The boys are at school, but I am back home in just over two hours after the play. I miss them and try to micro-manage over the phone, checking they have done their homework.”

Leo and Zac have not yet seen their mum on stage.

“Everything I have done is quite grown-up. They’ve seen a little bit of Call The Midwife and the little one couldn’t understand why I had another husband,” she says.

“I asked him once, ‘Would you like to do Mummy’s job?’ He said ‘No’

“I took them backstage when they were doing the checks for The Roaring Girl and there was all this smoke coming up from under the stage, and they were like ‘wow’. I hope it’s given them a sniff of greasepaint.”

Sharon looks in fantastic shape. She goes running, enjoys Pilates and took up boxing after having children.

“I do it with some mums. In the beginning every time I hit someone I’d say ‘I’m sorry’.

“I was running the other morning in Stratford. I was bright purple and a lady said: ‘Oh I know you – it’s Sharon Small’. It doesn’t happen in London. People are in their own little bubble.”

* Arden of Faversham at The Swan Theatre runs until October 2. Call 0844 800 1110 see www.rsc.org.uk/whats-on/arden-of-faversham

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