TO anyone who loves the Mamma Mia! musical - and who doesn’t? - the moment when Donna sings Slipping Through My Fingers to her daughter, as she helps to dress her on her wedding day, is quite the tearjerker.

There was barely a dry eye in the Alhambra when I saw Sharon Sexton, playing Donna, sing it - then she launched straight into The Winner Takes It All, the big emotional showstopper.

“With ‘Winner’ I can let rip and be emotional but with Slipping Through My Fingers I’m on the brink of emotion, and have to hold it back. It’s technically the most challenging song,” says Sharon. “The whole time I’m singing it I’m getting Sophie (Emma Mullen) ready for the wedding, it’s tricky vocally and every action is timed down to the last note. When Emma turns to me in her wedding dress, if she has tears in her eyes I’m gone. It’s a beautiful song, and it came from the heart - Björn Ulvaeus wrote it about his own daughter.”

Mamma Mia! is of course set to songs by Abba, and each one drives the story of Sophie, who wants the father she’s never met at her wedding. After reading her mum’s old diaries, she discovers her dad could be one of three men - so she invites them all to the Greek island home she shares with her mum, Donna.

“The jukebox musical has been interpreted many times since, but in this show the songs tell the story,” says Sharon. “And they’re often heartbreaking - there’s real life lived in those songs. There’s a pressure to get the songs right, because Abba’s music is so well loved. Bradford audiences are amazing, you can really hear them singing along. No matter what mood you’re in, you end up with a smile on your face by the finale.”

The show celebrates its 20th anniversary this year, and Sharon says the appeal is largely down to the music. “It’s not set in any specific time so it doesn’t date, and the music is timeless. It’s lovely to see different generations coming along, from four-year-olds to grandparents,” she says. “The show feels like being a Greek island for a couple of hours. I had a show watch a few weeks ago and it looked so beautiful; the lighting changes in such a subtle way, and you get this gorgeous sunset. All the costumes are made by specialists, even Donna’s dressing-gown and black slip are made for me which, as a performer, makes me feel special.”

Adds Sharon: “I love playing Donna; she’s a strong and vulnerable single mother, and there’s comedy and a wonderful love story too. She’s not expecting to find love again, and when she does it hits her like a train.”

And when Sharon sings those romantic duets with Sam - one of Donna’s three old flames who come back into her life - there is real love there. Sam is played by Sharon’s real life partner, Rob Fowler.

“We’re sharing a big adventure with this show. We get to fall in love again every night,” smiles Sharon.

The hit Mamma Mia movie spawned a sequel. Would that work on stage too? “Yes, I think so,” says Sharon. “Like the film, it would never be as good as the original, it’s a bit like the tricky second album, but it would work.”

Originally from Ireland, Sharon originated the role of Sloane in Bat Out Of Hell The Musical, winning a West End Wilma Award for Best Actress. Her other theatre credits include The Commitments, Billy Elliot and Anything Goes.

Earlier this year, with Rob, she toured a concert series, Vision of You, which has been nominated for a cabaret award.

She runs a theatre company, Biscuits for Breakfast, and is also a performing arts teacher. “I love the enthusiasm of young performers who are graduating and going into the business. It makes you appreciate your own landmarks,” she says. “I enjoy producing theatre too, but it’s nice to be in a show like this, as a performer, without wearing all the other caps offstage.

l Mamma Mia! runs at the Alhambra until November 23. Call (01274) 432000.