Tim Firth unveils musical This Is My Family

Evelyn Hoskins plays 13-year-old Nicky, with Rachel Lumberg as her aunt Sian

Sulky teenagers, stressed parents, overbearing in-laws - writer Tim Firth, who penned Calendar Girls, is singing the praises of the modern British family in a new musical comedy.

Thirteen-year-old Nicky dreams of having the perfect family. In an attempt to win an idyllic holiday, she writes a competition entry about her happy and harmonious household.

Except in reality it is not very happy and harmonious at all.

"They're not dysfunctional, but they're a normal family that's fallen into tramlines, emotionally and spiritually, and have their own problems," Firth says. "Nothing I hope any family in the country wouldn't recognise to some degree."

Nicky's family fortunes unfold in Firth's new musical This Is My Family, which opens at the Sheffield Crucible on Wednesday.

Firth, known for writing the screen and stage versions of Calendar Girls, the Madness musical Our House and the film Kinky Boots, says he thought it would be funny to base a comedy on "disastrous holidays that I can remember from my childhood".

Sian Phillips plays grandmother May and Terence Keeley is 17-year-old Matt

"That's where I started off," he says.

"But what it's evolved into, I think, is something about family and about what family means. What the value of it is, what the point of it is in an age when 50% of the family in any kid's class will be of a different structure - there will be parents who have gone apart and remarried.

"None of that I particularly intended."

Nicky - who is actually played by 25-year old Evelyn Hoskins - comes to realise that her clan, which includes her mum, dad, brother, aunt and grandmother, is in real danger of breaking up. So she tries to bring them back together.

Firth describes the story as "optimistic". As befits a feelgood comedy, it could come across as rose-tinted and idealistic.

The writer says: "There is this sense [in society] of, what is the point of families keeping together in a world which is increasingly telling you that, if you're not happy, you erase and start again? Get out, don't put up with second best.

Tim Firth's other credits include the TV drama All Quiet on the Preston Front

"There is a danger of couples forgetting what brought them together in the first place and jumping ship more quickly than they possibly need to.

"It's not for a moment suggesting that all families stay together - that would be unfair and unhelpful.

"But there is a sense within the story that this is a family that could have done that [broken up], but actually what they needed to do was to look inside for what was wrong."

The audience sees the family through Nicky's eyes. From the moment Firth wrote her first line - "OK, so this is my family" - he decided it would sound better if it was sung, and so the show became a musical.

Clare Burt plays mum Yvonne, Bill Champion is dad Steve and grandmother May is played by West End veteran Sian Phillips.

It is a member of the lesser-spotted breed of new British musicals that are not based on existing films, books or band back catalogues. As such, it is a tough sell and is starting out in the Crucible's cosy 400-capacity studio.

"Getting people to take a risk on coming to see a musical now is almost unheard of," Firth says. "We don't have that culture in this country.

"Normally they've been based on something people know. It's a movie or a back catalogue. There's something that removes the risk, and with this there isn't anything that removes the risk.

"This is a new story they've never heard of from a writer who's never really written a musical before in a studio space, so it's triple scary.

"The problem is that a lot of the time, a new musical, and especially one in a studio, people may feel that it's an experimental, discordant, scary new music thing. Which of course this show isn't.

"This show is very, very simple and I hope as accessible as a straightforward comedy. It just happens to take flight with music."

If This Is My Family does well in the studio, it may graduate to larger theatres. If it does not, it will not.

Firth's 2005 film Kinky Boots has been transformed into a hit Broadway musical

To illustrate the chasm between brand new musicals and adaptations, a stage version of Kinky Boots is currently sweeping all before it on Broadway, recently winning six Tony Awards. (Although it is questionable how many American punters have seen the original 2005 British film, for which Firth co-wrote the script.)

Firth has not yet seen that musical. "It's very strange," he says. "It's rather like having an adopted child growing up in another country. I'm not quite sure how much of him or her I will recognise when it returns.

"I went online and saw one of the song titles and thought, I'm sure I wrote that line. But I'm very proud that it's had this other life and it's great that they've made it a success because there are a lot of films out there and it's lovely for them to have seen it.

"And actually, more people know about the movie now than six months ago."

This Is My Family has a long way to go. The writer admits that there are "huge elements" of his own family in its characters. So will the Firths be going on a family outing to the show's opening night?

"Do you know what, we were going to be," he replies. "But one of the kids said, 'Actually, can I go to Milly's party?' So she will come on another night. That's what families are like."