WE'VE all mimed in front of the mirror clutching a hairbrush or attempted to emulate our musical heroes at karaoke, but for the 200 regulars on the Scottish tribute act circuit it's an altogether more serious matter.

They rank as some of the biggest earners on the homegrown entertainment scene thanks to their ready-made fanbases which allow them to sell out the best venues around the country. But can being part of a tribute act get you closer to that coveted rock star lifestyle?

BBC Scotland documentary series Viva Variety charts the reality of life for three such performers. Meet Rihanna impersonator Amy Craik, Doctor Sarah Kennedy, the frontwoman for Blondie-inspired Dirty Harry, and Peter McLean of Gallus Cooper.

DR SARAH KENNEDY

By day she is Doctor Sarah Kennedy, a respected consultant psychiatrist and transgender specialist. By night she morphs into the frontwoman of Blondie tribute band Dirty Harry, performing on stage for hundreds of fans.

Kennedy, 38, from Edinburgh, first coined the idea three years ago after realising it could help fund her other musical aspirations. She found four bandmates on Gumtree and Dirty Harry was born.

"It's a way to perform to bigger audiences," she says. "Starting out I saw it as a bit of fun and a way to make some extra money, but it has completely taken off as a separate entity."

In addition, Kennedy is a member of two other bands: Groovy Uncle featuring Miss Modus and Italy-based The Link Quartet. "It's hard to forge a career as an original artist," she says. "My work as a doctor is my main income and music is never going to compete with that. The way I see it, any money I make from Dirty Harry I simply re-invest in my other music. It's a complete indulgence."

Kennedy says that, for her, Debbie Harry ticks every box, describing the American-born singer-songwriter as a sassy lady and an exciting subject to emulate. "She is pretty provocative on stage, really energetic," she says. "If I went up as myself it would look like I was being egotistical whereas playing a role you can get away with so much more."

Kennedy's day job is as a psychiatrist and transgender specialist for Edinburgh and Lothians. "I work with anyone who has gender dysphoria or discomfort with their assigned sex at birth," she explains. "That includes, for example, non-binary gender where people don't want to be male or female, they feel uncomfortable, not quite sure and somewhere in between.

"The rest of the time I'm based in a general hospital as a liaison psychiatrist which can mean covering anything from self-harm by overdosing, cutting or burns to working with people who have become confused, depressed or psychotic."

She admits that every psychiatrist has probably self-diagnosed themselves at one stage or another, saying that she herself falls into "more the obsessive spectrum of things, pedantic and perfectionist" which are "ideal personality traits to be as an impersonator."

Her earliest memory of Harry is seeing Parallel Lines sitting in pride of place in her brother's bedroom. "It's such an iconic looking album and she looked so amazing on the cover," she recalls. "Everyone was fascinated by her and they were pop tunes you could dance to. I remember it first as a visual memory rather than an audio one.

"Later, being a frontwoman of a band myself, you start looking historically to other people and she seemed to stand out. She was interesting on stage and variable depending on whether she had a lot of drugs on board or not. I watched a lot of YouTube clips and gradually became more informed. I discovered a lot of her other music that wasn't on Parallel Lines."

Even with copious research, replicating Harry's style still poses its challenges. "Her most natural presentation on stage and in interviews can be quite flat," says Kennedy. "She is not someone who is overly colourful to watch, she's a bit more mesmerising and that's more difficult to capture because, unless you are that person, it's difficult to sell that on stage. So, I took on a bit more of her crazy persona, mainly from the earlier days when the band were punky than the glossier years of Parallel Lines."

However, Kennedy, who is married to fellow musician, Paul, 42, has a strict line on how far she will go.

"Sometimes Debbie Harry went on stage with" - she drops her voice to a whisper - "nothing on down below. Clearly I'm not going to do that. So it's about giving it a sexy enough edge, but keeping in mind the professionalism of my day job."

Being asked for her autograph is another common quandary. "I can't sign it as Sarah because if I do it looks like I've signed somebody's prescription," she says. "I signed someone's as Doctor Dirty but then thought: 'God, I hope the GMC don't get hold of that.'"

Getting recognised off-duty can equally bring its surreal moments. "I remember being at an airport once and someone came up and said: 'Oh, I recognise you off the telly,'" recalls Kennedy. "I thought it was about the music and was like: 'Thank you, that's so nice', but then she said: 'You were cooking a chicken.' I won the Scottish heat of Britain's Best Dish a few years ago. When I realised that's what she was talking about, I was so embarrassed."

AMY CRAIK

One spent her formative years against a backdrop of Barbados beaches and the other only a stone's throw from the golden sands of Troon where she still lives with her nan Mary. Yet for Amy Craik, her life has become irrevocably intertwined with that of global superstar Rihanna. Craik, who works in a chippy and dreams of becoming a social worker, spends every other weekend on stage emulating the woman she describes as "my idol since I was 13".

She got into the business after a family friend put her in touch with manager Scott Garvie who was looking for a Rihanna to add to his tribute act books.

Over the past three years, the 23-year-old has been in demand in far-flung locations including Dubai, Istanbul, Cape Town and Johannesburg performing her homage to the Bajan songstress. "I find Rihanna's voice very easy to imitate," she says. "I don't know whether it's because we're the same mixed ethnicity or because I grew up listening to her songs, but I find I can turn my ear to it no bother."

She is one of 10 tribute acts to the seven-time Grammy winning singer-songwriter currently on the Scottish circuit. While the real Rihanna is flanked by a sprawling entourage, Craik typically has her manager and two backing dancers.

Precision is everything. Craik can rehearse for up to 20 hours a week in preparation for an hour-long gig. She admits to "having a bit of an obsessive disorder" with getting the details right: "how she did that wee twirl or shook her bum there". With every performance, the goal is to do absolute justice to her music heroine. "There will be people who tribute that are absolutely bowfin," she says, sagely. Craik, who is half Caribbean on her father's side, was taught how to do traditional reggae dance moves such as the Dutty Wine and Butterfly as a youngster by her older cousins.

She can remember with pinpoint clarity the first time she saw Rihanna. "I was watching one of the music channels and Pon de Replay [Rihanna's debut single] came on," she recalls. "It had a reggae theme so straight away I was drawn to it. Back then she was this sweet and innocent pop princess. I've loved seeing her grow and change over the years. I have felt part of that journey."

When it comes to copying the singer's distinctive body art, Craik uses a combination of transfers and real tattoos. "I've got two tattoos which match hers anyway," she says, pulling her top over one shoulder to reveal the words: "Never a failure, always a lesson" inked below her collarbone.

Wigs are a key part of her costume. "Rihanna is a hair chameleon, she changes her style all the time so trying to keep up with her is a nightmare," she says, laughing. "Following someone who is so bang on trend is hard work, but fortunately there is always plenty of photographs out there of her whether on Facebook and Twitter or newspapers and magazines. There is no hiding from RiRi."

When she's not performing, Craik works in the Pavilion Cafe in Troon. She hopes to go to university next year to study social work. "Going on stage as Rihanna doesn't feel like a job to me, it's more of a hobby and something I love doing for fun," she says. "The fact I get to sing and dance? That's fulfilling a passion."

With her infectious enthusiasm, Craik comes across as a young woman having the time of her life and one who intends to savour every moment. "Rihanna's not going to be around forever," she says. "Well, she might be out there in 50 years time but in 50 years time I don't think I'll be getting up there in skimpy outfits and shaking my ass."

PETER MCLEAN

When it comes to plying his trade, Peter McLean admits that "shock rock on a budget" isn't always easy but in the quest for perfectionism he doesn't hold back. Among the more memorable props in his show-stopping set as Gallus Cooper - a canny Glaswegian take on Alice Cooper - are a 15ft-high gallows and 7ft-long boa constrictor called Scarlet.

McLean, 49, from Glasgow says it took "less than two minutes" to come up with the memorable band name. He has been part of the Scottish tribute act scene for the best part of six years. "I've always loved rock music and it's been a big influence since I was a child," he says. "I happened to cover a couple of songs by Alice Cooper. Someone said I sounded like him and the idea came from that. My favourite band is Kiss, I love the make-up and theatrical side to their performances.

"I got into Kiss when I was about 12, Alice Cooper was a bit later when I was 17 or 18."

While McLean, who works as a staff trainer, admits he would have jumped at the chance to impersonate his heroes Kiss, he concedes that Cooper is the next best thing and he's grown to love his alter ego. "I don't look like Alice Cooper but people judge it more on the vocal so that has to be spot-on," he says. "Whenever you go into a new venue, the people who own or run the place are standing around waiting for the sound check to hear that first song.

"I'm just some guy standing there with a T-shirt on, no make-up and my hair tied back, then they hear me sing and that's when they relax."

He's shared a stage with Cooper's original bass player Dennis Dunaway and guitarist Ryan Roxie - both who gave him the seal of approval. "That is definitely one of the best parts of doing this, getting to play alongside proper professional musicians who have seen it, done it and got the T-shirt," he says. "I was at a charity event for Nordoff Robbins and invited up to do a couple of songs with Ryan Roxie, who is Alice's guitarist. Standing up there with him then getting to go out for a meal and a chat afterwards was fantastic. He still keeps in touch which is nice."

Cooper would appear to have given his blessing too. "I've met Alice twice and he's a really nice guy," says McLean. "He has a good attitude and a sense of humour. He's been great about it. There has never been an issue."

McLean is married to Nikki, 43, a drugs researcher and they have three children. "It does take its toll on family life because I do a lot of organising for the band, from arranging rehearsals to booking the gigs which can be time consuming," he admits. "Nikki loves rock music too, though, so she gets why it means so much to me."

Given his line of work, the occasional odd request is perhaps inevitable. "We have done one wedding where they wanted the full show and that was surreal," he says. "The people were really nice and it was a good night but I found it quite strange. We're not really a wedding kind of band."

McLean concedes the Glasgow music scene regulars are a tough crowd to win over. "You don't get an easy ride," he says. "You have to earn their respect and it takes a bit of time to get people to buy into what you are doing.

"The tricky part is getting them through the door in the first place. Once they've seen you, it's fine. We've got a good following now and you do start to recognise familiar faces out in the crowd."

Convincing the music snobs isn't without its challenges either. "Tribute still has a cheese factor associated with it," McLean admits. "There are people on the rock scene who say: 'I only like the real bands, I don't like the tribute act.' I get that and everyone is entitled to their point of view, but usually the reaction we get when people come along to see us, they say: 'I hate tribute bands but you guys were fantastic.'

"Alice isn't going to be around forever and when he does finish, if you want to hear his music live, you are going to have to see a tribute act." n

Viva Variety is on BBC One Scotland, Monday, at 7.30pm