The cast and crew of Mamma Mia! are ready to bring the hit show to Hong Kong

There is a moment towards the end of the smash hit stage musical Mamma Mia! when three of the characters leave the stage in one set of clothes and, exactly one minute and 50 seconds later, return dressed head to toe in tight lycra costumes and platform shoes, with enough breath to sing a full Abba song.

"We have less than two minutes to get stripped off, into the lycra, get the boots on, take a swig of water and sort out our hair," says Geraldine Fitzgerald, who plays the role of Tanya.

"We have three people each to help us," explains Sue Devaney, who plays Tanya's friend, Rosie. "One person doing the shoes, one helping to zip the costume up and I've got someone taking my earrings, handing me my other earrings, sorting my mic ... and me thinking how am I going to get into my shoes when my feet are so puffed up.

"And then we just make it and we run on and the audience says 'Oh my goodness me, look, here they are again and they've changed. How did they manage it?' " Fitzgerald says.

Both actresses have been playing eight performances a week for three months over the summer in Blackpool, England, and will be coming to Hong Kong in mid-September for a six-week run of the same production.

"We'll have buns of steel by then," Fitzgerald says. "We have to go up 70 stairs to our dressing room each time, and we're not allowed to use the lift during the show in case it breaks down."

Devaney adds: "Imagine if it broke down when you were due on stage, and you just didn't appear."

Mamma Mia! was designed as a so-called jukebox musical: to show off the songs of a single band, in this case of Abba, the 1970s chart-topping pop group from Sweden. However, since it premiered in 1999, it's clear it is much more than that. It doesn't mention Abba at all, instead it is about a young woman, Sophie, brought up on a Greek island by her mother Donna, and never knowing the identity of her father - until one day when she finds a diary that suggests three possible dads. So she invites them all to her wedding without telling her mother or fiancé, Sky. And so as they all (including Donna's two best friends, Tanya and Rosie) gather on the island, the fun begins.

Sophie is played by Niamh Perry, a 24-year-old actor from Northern Ireland, who first became known in Britain for her performances in a 2008 BBC competition to find someone to play Nancy in the musical Oliver! She was 17 at the time, and had to study for her A-levels while learning six or seven songs a week. She didn't win the role, but a year later was offered the role of Sophie in the West End.

"That was my first job; taking that role was like going to drama school for me. I was a total beginner and learned so much," she says.

Because it was her first job she was nervous about admitting to be ill.

"I used to get this frozen shoulder and there was one time when my shoulder was strapped up and I had to wear this wedding dress, so there was me and a strapless wedding dress and loads of tape all up my neck ... you would definitely have been able to see."

The story, written by the then-unknown Bristol playright Catherine Johnson, is a simple tale of love, friendship, families, a Greek chorus and a question of paternity, but it is charming and sunny and it has clearly struck a chord.

According to the producers, it has now been seen by about 55 million people (including Hong Kong back in 2004), in 14 languages and 39 productions (not including the 2008 film starring Meryl Streep and Amanda Seyfrield, which grossed more than US$600 million worldwide). There have been, apparently, so many orders for high quality lycra garments coming in from all of the productions of Mamma Mia! around the world (each show needs about 500 costumes, although not all are lycra) that the show apparently saved an Italian fabric mill from going out of business.

The show is something of a family enterprise for Sara Poyzer, who plays Donna. Not only has her younger sister Claire also played the role ("She did the tour and I did the West End then she did the West End and I did the tour") but her husband, Richard Standing, plays Sam, one of the dads (played by Pierce Brosnan in the film).

"The thing is with the dads," Standing says, "is that we get talked about an awful lot and we seem quite important but we actually don't do much. It's like the kings in Shakespeare: first it's 'the king's coming', then 'who's the king', and then, 'well that was the king, so what did he say?' I sing one and a half songs. Sara sings 16 or 17, there's a big difference."

The couple met while working on Shakespeare's The Merchant of Venice. "We were Gratiano and Nerissa - the idiots who fall in love, and that's what happened to us. We fell in love."

Standing went to see Mamma Mia! because Sara was in it, "and before I sat down, I thought it was not aimed at me I'm not its natural audience, but like every other forty-something in the audience you watch and think, 'I'm quite enjoying this'. And you're quite moved in the second half, and by the end you're up and dancing. I saw Sara doing it and thought, 'I'm not a terrible singer, it looks like fun, I should try'."

They had performed together before, though it's never a given that a married couple will be hired to play opposite each other. "Friends of ours auditioned recently, but the director said the chemistry just wasn't there, and they'd been married for 12 years," Poyzer says.

They are still intrigued at one of the questions they were asked in the Philippines when Mamma Mia! was staged in Manila in 2012.

"They wanted to know how I felt playing a woman who doesn't know who is the father of her child," Poyzer says. "In the UK you don't really think about that any more, it's just a plot device. But the Philippines is a country where you can't get a divorce. And so something which to some people might seem a light musical comedy suddenly became this serious issue."

The tour started last November in South Korea (where it is so popular there's a phrase "she's so Mamma Mia", to describe a strong independent woman such as Donna). And on the first day in the country, several members of the company found some serious fans on the Seoul subway.

"Someone asked if we worked for an English school," says resident director Nick Evans. "I said no, we're doing Mamma Mia!, and she shrieked. She was so obsessed with the show. She looked at the actors and said, 'I should have guessed, they're very beautiful'. Then she turned to me, looked at my face and asked, 'are you the director?' "

Mamma Mia!, September 24 to October 26, Hong Kong Academy for Performing Arts, 1 Gloucester Rd, Wan Chai, HK$395-HK$995, HK Ticketing. Inquiries: 8203 0299