The actress-singer would normally be forthcoming about the roles she plays, whether appearing as Nancy in Oliver! in London's West End, or alongside Marti Pellow in Jekyll And Hyde.
But the Carntyne-born entertainer is entirely tight-lipped about her current part, appearing at the Theatre Royal in One Man, Two Guvnors, the comedy play that stormed London last year and made a theatre star of James Corden.
Corden is not in the lead role this year, but we do know that Rufus Hound is.
What we don't know is who/what Sabrina plays.
"I can't say too much about my part because I'm sworn to secrecy," she says, smiling.
"If I tell you who I play it will give the story away. It will spoil things. But I can say the story is a complete farce from start to finish. It's great fun."
The play, by Richard Bean, is an English adaptation of the classic 18th-Century Italian farce A Servant Of Two Masters. Italy is replaced by Brighton in 1963 and tells the story of struggling Francis, who gets one job and then another, because his plan is to eat. But before long, Francis is working for two Guvnors, and hilarity ensues.
"There is also the back story of Roscoe being a gangster and he is murdered and his sister dresses up as a man, and it's all very silly," says Sarbrina. But you'll love it."
Most likely. The play opened at the National Theatre last year, toured in the UK and has also been a hit in New York with a Broadway opening in April 2012.
However, Sabrina, who trained at the Royal Scottish Academy Of Music and Drama, admits she had some misgivings about joining the show.
"I'm used to singing all the time," she says. "So I faced this question of, 'Do I do another play, and go for six months of not singing, not keeping my voice up?'. Then I thought, 'Well, it's a great play, so do it'."
Sabrina loved the notion of becoming an entertainer from an early age. The family moved from Glasgow to Durham and her parents hoped she would 'do something serious' with her life.
"My family come from a retail background and they reckoned acting was all very willy nilly. I'm sure they worry about me."
But Sabrina knew she wanted a life on stage. She came back to Glasgow and joined an 'am-dram' company.
She says: "Before I went to the RSAMD I joined The Pantheon, and really got into the flow. And it was fantastic. It was full of nurses, people who worked in schools who don't take it too seriously, but have a good laugh.
"You get the range of talent, people who are brilliant, some not so brilliant. It's a great training ground and you get to play the King's and the Theatre Royal – and the chance to see what it's like to sing eight times a week."
But Sabrina was never tempted by retail, although she says with a smile: "There may come a time -
"You never know when your next job is coming along. It's hard and you can lose your confidence. However, I have been lucky. I have gone from job to job. Most actors work in bars, but I have not had to do that for the past five years."
Sabrina admits acting life is odd. "It's strange, but we're so lucky. To pretend to be someone else is great. I say I'm a professional liar when people ask me what I do for a living. And I love it because it's easier to be someone else.
"I hate to go out at night and end up singing on stage. That means me being me. I don't know what to say what I am up there.
"I hate the pressure to be funny and end up saying stuff like 'Hi, thanks for coming'. I prefer to have a spotlight, and the script."
Sabrina admits it was strange to be working with Marti Pellow in Jekyll And Hyde. "He was lovely, so down to earth. My mum used to play his cds all the time, and here I was working with him.
"But he was really fun to have around and you could tell he had had to work for success. Nowadays it is all about instant fame."
Sabrina, whose husband is a freelance drummer, understudied the role of Nancy in the West End, but she has no great desire to return to Oliver! as the leading lady. "I got the chance to play her so many times," she says. "I've been bludgeoned to death quite enough."
"What I would really love is to come home to Scotland to work. But the scene is not big enough. While The National Theatre of Scotland is thriving, I have never been able to audition, thanks to the fact I have been working solid."
Sabrina's family are now back in Scotland and living in Bishopbriggs. Yet, she has not told them what to expect from her Two Guvnors role.
"I can't even tell my family who I'm playing," she says, in hushed voice.
"It will have to be a surprise for everyone."
l One Man Two Guvnors is at the Theatre Royal until Saturday.