SHARON Small has long suggested several big questions; how has the Scots actress come to be almost a telly constant? Since landing a key role alongside Michelle Collins in the 2000 drama, Sunburn, Small has featured in series after series, becoming part of a band of major talent.

The actress who grew up in Clydebank and then Kirkcaldy has played a range of English and Scots characters in the likes of Mistresses and the more recent Trust Me, alongside Jodie Whittaker. Next year she’ll star in a new cop drama, London Kills. What is it down to? Hard work? Sheer talent? A steely determination to become A STAR?

“What are you hinting at?” grins the blonde actress, sipping tea in her dressing room at the Edinburgh King’s Theatre (where she’s been appearing in Still Alice – more of later). Well, Sharon, you’ve had a career most actresses would die for. What separates you from the rest? “I’m not sure what you’re asking me?” Well, I guess I’m wondering if you had an easy familiarity with the casting couch principle? Thankfully, she takes the joke and bats it right back. “No, I wish that opportunity had come up! I might have been further along the line,” she says, laughing.

She adds, in more serious voice; “Okay, I’ve had a degree of luck in landing returning series.” A degree? You’re omnipresent. “But the reality is there are six or seven names in the frame for the top jobs (on British television.) I’m not in that category. I get to play the sidekick, or the supporting role.” But you get these roles continually. You work harder than a Brexit civil servant. “I guess I do,” she concedes. Okay, so dry your eyes, then, Sharon. Thankfully she laughs again. Which partly indicates why Sharon Small has had so much success. You sense a great team player.

More of a clue emerges however when she recalls how she came to be starring in The Inspector Lynley Mysteries series that kept her on our screens for six years.

Small’s character, Sergeant Barbara Havers, was described in the script as “someone who is an obesely fat and an unattractive woman from Acton in west London.” Now there’s a challenge right away, Sharon. “You’re right,” she says, grinning. “I never even expected to get to read for the role, but the producer had seen me in something and she was keen to see what I would do with it.”

She breaks into a laugh. “But the really important thing about the part is that the character had to be someone the Earl (the Inspector, played by the handsome, smooth, Nathaniel Parker) wouldn’t want to sleep with.”

So you had to be able to convince as rather unattractive and unbedable? Was there part of you hoping someone would say ‘Sharon Small is too gorgeous for this role?’ “Well, yes, no, not really,” she says, smiling. “But that character description of Havers was my staring point. What that told me was I knew my character had to have low self-esteem and she was lonely. But that she covered this up with seeming a bit feisty. And I knew enough from my own psyche that I would be able to tap into that.” Small clearly has the talent to make casting directors see beyond physicality. So she’s really five feet five inches of feistyness, which is really a shell covering for vulnerability?

She laughs again, suggesting a woman who doesn’t take herself too seriously. “I got the part but I had no idea the show would run and run, and of course my character had this London accent. I could do it a little but I found the accent really hard, especially when the scripts would often arrive late, so there was little time to prepare.”

No matter. Small, who had begun to hint at film fame in the likes of Bumping The Odds in 1997, (Best Actress, Edinburgh Film Festival) was now a household name. Was that the dream growing up? Did she always want - need? - to be an actor. “I was a busy kid,” she reflects, smiling. “My best pal has since told me I never stopped dancing - that I looked like an idiot. But I didn’t realise I was doing it.

“And I remember when I was young, watching a programme about kids who had gone to stage school and going through to my mother and asking; ‘Mum, can I do that?’ And she looked at me and said ‘Whit? Shut up. Go away and play!’ And I can understand that now because we had no money for ideas like that.

“I never asked again. But aged 15, I was in physics one day and my teacher asked what job I wanted to do. I said ‘I think I want to be an actress.’ But I’d shown no real talent or indication I could do that.” Yet the inner performer was lying in wait, ready to be unleashed? “I guess,” she grins.

On leaving school her careers teacher suggested Small join the Marks and Spencer trainee manager programme. “I think our teaching has been pushed into a corner,” she offers. “They are not allowed to teach vocational subjects, to see what the best way for that child to learn is.” Or to try to work out the best career path? “Exactly.”

Did her parents encourage her towards taking the acting foundation course in Kirkcaldy, where she lived during primary school years? “My mum would always try to play safe. She taught us (she has four younger siblings) to fly, but she’d rather we hadn’t, that we’d be around the corner, close by.”

The 52-year-old references her mum Sandy a few times, but not her dad? “Can I not talk about him?” she asks, in a voice which suggests pained memories. “It’s just really complicated. But essentially I was brought up by mum.” She adds “She’s 70 next year. She had me young.”

Small went on to study at Mountview College in London. Did the fact she hadn’t been involved in youth theatre etc result in approaching drama college with less confidence than her peers? “At drama school you are told straight off most of you won’t make it. But I had this feeling in my head I’d better make sure I’m not one of the drop-outs.”

Ah. Determination. And the drama school experience demanded it. “I just couldn’t get the straight roles in college,” she recalls. “I got cast in musical theatre, which I didn’t really want as a career, or little old ladies. As a result, when it came to the graduation showcase I was this anonymous little old lady on stage. None of the agents wanted to know.”

Small made sure she was seen later, by appearing in a solo slot in London’s West End, where she performed a piece Marco Polo Sings A Solo. “I performed it in my own accent, which wasn’t really done at the time. And landed an agent.”

Her career was on the move. Not an E-Type, fast car race forward, more a sluggish transit van, as she joined rep theatre and toured the country. Her first job however revealed huge resolve - and ability to think on her feet. “It was in Pitlochry, in rep theatre, and the company were doing Arsenic and Old Lace. One of the actresses had an accident so I had to go on playing an old lady in a costume and a wig that was too big. But I didn’t know the part. I had to read from the book.”

Was she terrified? “Not really. It was a thrill, just to get on stage. I was 21. I had that bravado you have at that age, but at the same time I had the realisation ‘I’ve just got to do it.’

“But the director and the rest of the cast forgot a very important point; some of the scenes in the play were in near darkness.” Which meant the little old lady couldn’t see a word of the script in front of her.

“The rest of the actors just moved me around the stage,” she laughs. “But after a couple of days I’d learned the script and ended up playing the character for three months.”

It took five years before her career picked up speed, taking her in the direction of television. Yet while the past 18 years represent a career success story – with the likes of film roles in About A Boy and Dear Frankie – can she handle the rejection that comes with the job? “There are lots of knocks to take in real life but ours are ‘Sorry, you’re rubbish’”, she says, with a wry smile. “And you have to remember that most people have interviews just a few times in their lives. We do it all the time.”

Did rejection ever lead to tears? “Oh yes,” she says in an emphatic voice. “I got told ‘No’ three years in a row, just before Christmas, which is a regular time when you get the results of auditions. And I remember one Christmas, on December 18, I actually got four ‘Nos’ in the one day. How I cried that day! (She acts wailing) ‘What is wrong with me?’”

The actress adds; “I’ve learned since you can lose a job by the nearest whisper, although at the same time, don’t get me wrong, you can sabotage yourself at an audition.” In what way, Sharon? “I remember once, just after having a baby, (Small has two sons, Leo and Zac, with photographer partner Daniel Bridges) I saw a director for a job and was asked what I had been doing recently. You know, the truth was my head was full of nappies and feeding, but I couldn’t for the life of me think what to say. I just babbled. Job gone. And I can remember taking Leo to auditions and asking someone to hold him for me while I read.”

Sharon Small laughs easily. And there’s an evident self-awareness and intelligence. It’s not hard to see how she became a National Theatre star. It’s not hard to see why she was cast in her current role in Still Alice. This stage version of Lisa Genova’s book tells of Alice, a 50-year-old Harvard professor with onset dementia, (Julianne Moore picked up an Oscar in 2014 for the film role) is a hugely demanding part.

Her character has to be able to look inward and speak to herself. “I miss myself,” says Alice. Small says it’s an immensely rewarding piece to do. “When you get an immediate response from an audience it reminds you why you do this job.”

Does the subject matter frighten her? Michael Caine said recently he couldn’t play someone coping with dementia – it was too close to home. “I felt I could do it,” says Small. “But I worked with Wendy Mitchell, our consultant (who is coping with dementia) who was honest with me, she helped me get the eyes, the walk right, and when I got the seal of approval from her I felt okay. But I have to add this is a bespoke story; it’s not everyone’s story, although there is a real universality about it.”

The play has had a powerful impact upon audiences. “One man came to the show, a dementia sufferer, who said he loved it. But then smiled as he said he wouldn’t remember it the next day. One lady left during the show, it was too much for her, but then returned. And she came back to the stage door later and said she’d taken so much from the show, a real sense of love.”

The play has really brought home the impact of the illness. “It’s scary. We’re living longer. The plaques and tangles begin to cover your brain and affect people in different ways. Some get angry. Wendy however says she’s forgotten how to be angry.”

Just before this chat, a news story appeared suggesting a possible cure. Has she read it? “I have it in my dressing room,” says the actress, clearly clinging to hope.

Small has picked up great notices for her performance. But the chat reveals a woman who, despite a great career, doesn’t quite see it that way? “Yes, life is good but there’s a sense I’ll never be Juliet,” she says, with a wry smile. “And I haven’t done the indie film that lifts you up into the stratosphere. It’s the very beautiful women who get that chance. I was never that sort of person. I’m too . . . curvy.”

But isn’t that better in the long run? “Yes, well, maybe. But if you’re Oscar nominated you tend to stay in the frame for good work.” Has she done the casting rounds in LA? “I did it once, still full of breast milk at the time,” she says with a little sigh, “and I didn’t really know what I was doing back then. But I’d love an American TV series.”

Life outside of theatre and television is good. Small talks animatedly about her two sons. “Thankfully Dan took over a lot of the parental responsibilities when I’ve been working.” She grins; “I’m sure they’re happy when I go off to work. I’m the strict one, ‘Come on, get your homework done.’ Their dad is so laid back.”

She reflects on the changing concept of childhood. “They’re not daring themselves to do stuff. So much of our lives was about getting out to play. You’d go out, come back when you’re hungry, for a piece. You had a bath once a week, all sharing the same bath.” She laughs; “Dirty water. That’s what I remember. Now, kids’ lives are all organised play dates.” Her laugh becomes louder and mocking. “And kids have showers!”

After Still Alice, Small has nothing (yet) in the diary. “I get depressed when I get to the end of the job because I know I have to go audition,” she admits. “And it gets harder as you get older. You do want it more. But there are less roles. And so many good actresses out there.”

Her success, you surmise, is partly down to the fact she loves to work. And now Small wants to have more sex. “We need to see women over 40 as sexual beings,” she explains, with a wry smile. “Most television dramas feature relationship stories. Couples having sex. But for some reason TV doesn’t seem to recognise that older women like to have sex too. It’s not great to be seen as a non-sexual being. That’s why I liked Mistresses.”

But you’re working at the moment, in a great play, Sharon. There’s the new telly drama out next year. “Do you think I’m dead moany?” she says, with a little worried smile. Yes. Dry your eyes, Sharon.

She breaks into a laugh. “Okay, but if you see me in three months and I’m out of work (wailing voice) ‘Nobody wants me, I’m useless!’ then you’d better show more sympathy.”

*Still Alice, The Theatre Royal, Glasgow, November 13-17.