WAIT a minute; it’s 30 years since girlband Eternal formed. Yet, one of its members is not only still capturing headlines, she also continues to expand her career.

Louise Redknapp has reinvented herself several times in her professional life; from singer to television presenter, from lingerie model to Strictly star to songwriter.

But now she has given her agent yet another reason to warm his hands with glee.

The single-name star, who enjoyed a successful stint in the musical theatre world with the office misogyny tale, Nine to Five, has become a straight actor.

The south-east Londoner is starring in Fatal Attraction, the stage adaptation of the 1987 movie which starred Michael Douglas, Glenn Close and Anne Archer. Redknapp plays Beth Gallagher, the wronged, teary-faced wife.

But hold on, Lou. You’ve sold 15 million records worldwide, you’ve proved you can be successful across the career spectrum, so why take on straight theatre? It’s tougher than Tory immigration policy. And you could be relaxing back at your lovely Surrey home with your two teenage boys?

“Theatre is hard,” she agrees, with a wry smile. “You can’t just show up for a couple of hours. It’s a challenge. But I love performance. It’s what I’ve done from a very early age and to be honest, if I’m not performing, I feel like a shadow of my former self. Part of the way I build up my confidence is by working.”

Louise Nurding, as she was before marrying former footballer Jamie Redknapp, was just 11 when she won a scholarship to the Italia Conte Stage School in London (where she met her future Eternal band member, Kelle Bryan, on her first day.) Later, aged 15, Louise was approached by a music producer with plans to form a girlband.

Eternal were massively successful. In 1998, the second album went platinum. Louise was on the cover of magazines such as Smash Hits and GQ and voted Sexiest Woman in the World by the readers of FHM magazine.

But most groups implode and Louise, by this time married, scaled down to solo performer and single name. The albums sold well, and along the way she tested the waters of new careers, such as TV and radio presentation.

However, she understood implicitly that the industry constantly seeks new faces. “I learned you have to work hard to maintain success. You don’t stay in this business for 30 years without putting the graft in.

“And to be honest, I’m really grateful for this opportunity. I’m not getting any younger. (She’s 47) This [job] could have passed me by. While having my kids and during my marriage I did the minimal amount of stuff so in getting this chance I’m going to grab it with both hands and run with it.”

Redknapp is certainly committed to the project. She watched the movie three times before beginning rehearsals “to get a sense of my character.”

She adds: “I’ve done bits of it over the years, but the priority had always been music. So, the world of straight theatre has taken a bit of getting used to. And to be honest, when this opportunity came along, I wasn’t sure if it were right for me. But then I met the director and it felt good, and I’ve really loved this idea of learning something new every day, getting into the character.

“I’m not just going out there and delivering lines. I’m also reacting to the other person on stage who like me is perhaps going through a different emotional experience that day.”

Was she nervous on opening night? She laughs, suggesting that that was certainly the case. “Normally, I walk on stage to the sound of an orchestra or a band. This time I walked on the sound of my own footsteps. Yes, I get nervous, but there is also an element of excitement. I guess it’s because I love the challenge.”

But there’s more. The performer wants the applause. “I want people to like me, to walk away from theatre and say ‘Oh, we knew her as a singer, but she was great in that.’ I want people to feel something, to connect with their lives and for them get the tingle. I want to give them honesty.”

Sadly, much of the focus on Redknapp in recent times has been predicated by the break-up of her marriage to Jamie Redknapp, who has now re-married. Does she enjoy the opportunity to leave Louise Redknapp behind in the dressing room for two hours every night?

“Yes. People think they know me because of my name and what’s attached to it. “I’ve had a fair load of bad stuff thrown at me. Life hasn’t turned out 100 per cent the way I may have planned it. And I get the criticism on Instagram. So, it’s nice to lose all of that for a bit. It’s nice to become a different character.

“When you’re in a musical like Nine to Five, you’re singing out to an audience. In this play, I’m talking to someone on stage.”

She laughs again: “It’s nice to not break into song. Now I can be someone else. Then a couple of hours later I’m back at home stacking the dishwasher. Back with my boys.”

What do her boys (Beau and Charley) think of her Fatal Attraction performance? “Typical teenagers!” she declares, grinning. “They keep saying ‘Yeah, we’ll come.’ But they haven’t.”

She affects complaint. “You know, I fit in my role as a mum. I do the school runs. I make sure I’m there for them.” She smiles. “But all I want is they grow up to have a good attitude to work and life.”

Fatal Attraction, the movie, was a global hit. But can the storyline of a jilted woman’s revenge still hold the same attraction today? After all, the central character suffers from mental illness.

The play's director, Loveday Ingram, admits it’s a subject that has to be handled far more cautiously these days.

Louise Redknapp adds that the play – set in the modern day and as such will feature the technology of the moment, such as mobile phones – will offer up surprises. “The ending is the original ending of the script, which was filmed. But the studio bosses then wanted a different ending. And this play’s ending is the original.”

What is guaranteed is that Redknapp’s enthusiasm is unbridled. If enthusiasm alone can guarantee a major theatre award, she’ll have heavy arms carrying them home.

“I appreciate the chance I’m getting,” she says, smiling. “And at the same time, I love the experience. I’m having a great time.”

* Fatal Attraction; The Theatre Royal, Glasgow, April 18-23.