EILEEN Nicholas produces a mock sadness when asked if she’ll be reprising her role in 1996 cult movie Trainspotting when the sequel opens next year.

“I’m dead,” she says deadpan of her part as Renton’s mum, played by Ewan McGregor.

“All that’s left to remind the world of me is a photograph on the sideboard.”

The Govan-born actress adds, grinning; “And I don’t imagine I’ll be getting royalties for that appearance.”

Trainspotting’s loss however is Oran Mor’s gain. Right now, Islington-based Eileen is starring in this week’s play, Del Gesu's Viola.

Hector MacMillan’s play, which also features Peter Kelly, Finlay Welsh and Elisabeth Flett on violin, tells the story of the disappearance of a world-famous violin.

“The debate is about the quality of a violin rather than the value,” says Eileen who plays a procurator fiscal, the play set during a precognition trial.

“A dealer (Finlay Welsh) claims he has been duped by the seller (Peter Kelly) and I have to decide if there is a case of fraud to be made against the maker.

“The question being asked is how do modern instruments get into the market if the dealers are promoting the older ones as the best, raising the value?”

It’s clearly a cerebral piece. “Yes, and I’m having to do a lot of thinking in this role. My character is impartial and I’m asking the questions the audience will be asking.

“But there is also comedy coming out of the characters.”

Eileen’s character has no name. But she’s given her one, nonetheless.

“I call her Marian,” she says grinning.

That detail tells a great deal about the actress. Indeed, Eileen takes her profession more seriously than most.

Despite a huge theatre career, in rep and stints at the Traverse, and having starred in television series’ such as the Borderers, Eileen went back to study acting at the end of the century.

“I went drama school in Islington,” she reveals. “There were questions I was asking myself; how to find my characters, how to create one.

“I wanted to create the person who is in the play, to live the play and to think the thoughts of another person.

“I wanted to be able to do all this and not think of what is going on in your own life, whether it’s divorcing your husband or whatever.”

Eileen never grew up hoping to act. It was when a boyfriend at Shawlands Academy went to drama school, he encouraged her to do likewise.

Backed by a former supervisor at Socialist Sunday School, Eileen found herself accepted by Glasgow’s RSAMD.

Yet, even after decades in the business, Eileen never saw herself as the finished article.

“When I got married and had two children I didn’t have the time to act. But my husband was the RSC and I got to watch other actors.

“I began to realise actors are there to tell a story. It’s not about doing little fireworks acting as some people do.

“The critics notice this sort of acting, but it doesn’t mean it’s being done properly.

“I reinvested in myself by studying with a Russian teacher. You know, the East Europeans treat theatre much more seriously than we do.

“And we learned circus skills, dance, how to become a capable all-round performer.”

She adds with a satisfied smile; “I can now juggle. And I can walk on stilts. I can stand on my hands.

“I realised there was a lot of fear in me. But this experience let me take my own lid off.

“Now, I enjoy my life and my profession so much more.”

The Oran Mor audience will be able to appreciate Eileen’s reinvestment in her career, and the clear enjoyment in her intelligent performance.

But what of her very first television appearance? How much did she enjoy that?

“Oh, you mean my Benny Hill,” she says, grinning of the 1968 role.

Yes, Eileen. Were you a Hill’s Angel?

“I guess I was,” she says, grinning.

“I came on in a catsuit, riding on a motorbike, But I’m very proud of it. It was my first job in television and it was filmed live, so I had no idea who I was to talk to – the person or the audience.”

The actress adds; “But you know, I’ve never seen myself on it. I must get onto Amazon and see if it’s there.”

• Del Gesu's Viola, Oran Mor, until Saturday.