English gent Colin Firth is an expert at making millions of females swoon. He stole hearts when he dived into a pond in just a white shirt and a pair of breeches as the aloof Mr Darcy in Jane Austen's Pride and Prejudice. But it was his role as Mark Darcy in the Bridget Jones' s Diary movies that secured his place as Brit rom-com king.

"When I look in the mirror I'm glad that women feel that way about me. It does give me confidence," he admits.

"Saying that, I do not have extreme fans. I haven't been chased down the street, and nor has anyone ever thrown their underwear at me.

"My wife Livia certainly wouldn't go weak at the knees if I came home in a sodden shirt! And I've certainly never seen myself as a sex symbol."

But he is just that. And despite throwing himself into dozens of different 'romantic hero' roles since Mr Darcy, Colin says that, 12 years on, he still cannot shake off that character's legacy.

"I've spent years trying to figure out why Mr Darcy's fully-clothed swim in his breeches and shirt caused such a sensation. I still don't know what it is all about. But he has led me to more work.

"I don't care if I frequently play romantic roles. I don't do anything to avoid it. I am quite happy to fall back into those roles.

"I like an easy life and they're paying me," he laughs. "You know, I don't want to do more work than is necessary."

"Mr Darcy got my name recognised but it also put me in a box. It made me feel a bit of a star, but 12 years on, it feels like a school nickname you can't shake.

"I know that Mr Darcy follows me around. He is how I made my name so I have learned to embrace him and live with that fact.

"If you start a character all loosened up, you have nowhere to go with it. But if you begin with the uptight man, the audience can enjoy watching as he slowly lets go and unravels."

In his new film, Mamma Mia!, Colin's character does just that. The film uses the songs of supergroup ABBA to tell the story of a young girl who is about to get married and decides to track down the father she never knew.

Getting back to his rom-com roots, Colin, 47, disco-dances his way back onto the big screen when he plays and sings one of the possible fathers, banker Harry Bright, alongside fellow fathers Pierce Brosnan and Stellan Skarsgard, while Meryl Streep plays her mother.

"I had an absolute ball making this movie. I spend my time almost entirely in the UK," says Firth. "So being able to go to Greece for this shoot was amazing. I think it was one of the best summers I have had in my life.

"But it is not an easy thing to portray that fun and party atmosphere on screen because the whole process of filming is so repetitive.

"Luckily, on this occasion, I was working with a group of people who are all quite naturally silly, so there was a real readiness for fun. A lot of us lived through the Seventies when ABBA were in their prime -- so we all had that to share."

He insists he was never a huge Abba fan when he was younger, which made it harder for him to get to grips with the music for the movie: "I definitely was not a fan," he says. "I think most straight males of my generation were not. I took myself incredibly seriously when I was younger. When I was young, if you liked songs like Waterloo or Super Trouper, you kept it to yourself.

"I know I had a certain fondness for Abba -- and I definitely fancied the two girls. I kept changing my mind between the two as to which one was my favourite, depending on what they were wearing.

"Admittedly, it is very hard to resist Abba when they get going, particularly when you see the energy and exuberance that is delivered with it in the film.

"Even if people are rolling their eyes at the first bar or two of the music, they will have to be a very churlish person still to be resisting it by the end."

With all the foot-tapping and disco dancing, what did Colin feel about singing in this movie? Not to mention the daunting prospect of having to wear Lycra.

"It was like there was a big party coming to town and I did not want to miss out," Colin says of the filming process. "Singing or not.

"And considering I put on a blue spandex suit and made an arse of myself, I had a great time. I think, in a way, middle age is quite liberating. If you have some unpleasant contours appearing on your body -- why not show them off?"

Even though he hit the right notes in this film, Colin says it is unlikely he will ever be asked to sing again.

"I do sing in Mamma Mia! It was scary and I think this movie will stop anybody ever asking me to sing again -- on or off screen."

But despite putting down his vocal abilities, there is one thing Colin knows he is good at -- fatherhood. He admits that playing a father-figure in this all-singing, all-dancing extravaganza came naturally to him, thanks to the strong bonds he shares with his five children.

"I had plenty of practice at being a dad before this film. I have two step-kids, one who is 23 and one who is 21, and I have a nearly 18-year-old son and I changed his diapers, and I now have a seven-year-old and a four-year-old."

Giggling, he adds: "They are out of diapers just in time for me to start changing my own."

But the years have been very kind to Colin, who admits that he is now more popular than ever with the women. And that goes hand in hand with being more popular with the paparazzi, too.

"I have noticed them more and more. But in the grand scale of things, I tend to be left alone.

"Unless you somehow have the terrible misfortune to attract more attention by means of scandal or something, the media tend to know to leave you alone. They leave me alone because I am too boring.

"There was a period when it was intense, but I am just not a story anymore. Sometimes it surprises you, when you have the grotesque experience of playing with your kids in the park and then finding five days later that someone was taking photos of you the entire time. We are quite lucky really because that sort of thing has not happened for a while.

"I am lucky. I would find that absolutely insufferable. I do get gossiped about, I read little things, but you can never win a battle of correcting everything. Fortunately most of it is not harmful enough to warrant doing anything about. But, you know, I've had it very, very easy in that respect."

But Colin admits there have been times when the shutterbugs have been less than welcome in the Firth household.

"Actually, the time I met my wife, there were two years between that and us getting married, when we would be followed quite a bit. It was around the time of Mr Darcy so they were interested when I started a new relationship and wanted to find out who my wife was.

"We once had quite an exciting chase through Rome. The photographers chased us on motorbikes. That was pretty intense and we've all seen how that can end up.

"We were actually racing through the streets and the tunnels. My wife was driving and she's quite a driver. It was a white knuckle-ride for me, I can tell you."

The last year has been a hectic one for the gorgeous English gent. But if Mamma Mia! is the summer blockbuster it is expected to be, Colin admits he could find himself more in demand than ever.

"One of the things that has taken up a lot of my time is a documentary that my wife Livia produced, and that I co-produced with her, called In Prison My Whole Life. It's a documentary about a prisoner on death row in Philadelphia; there's a racial element to it and this guy was accused 26 years ago now.

"He's a black man accused of shooting a white policeman. It led us into some very interesting territory. So last year was spent interviewing various people, one of whom was the rapper Snoop Dog.

"So one minute I am sitting in a room interviewing Snoop Dog and the next second going to the set of Mamma Mia! dressed in spandex and then flying to Italy to shoot Michael Winterbottom's film Genova, which is about death and grief, and then kissing a transvestite Rupert Everett in St Trinians.

"It was quite a kaleidoscope of an experience this last year. And I have another busy year coming up too, but I just wonder if it will be as diverse as this last one!"

- Maggie Ryan