AUDIENCES should watch out for the burp when they’re watching Matilda The Musical next week. For writer Dennis Kelly, who co-penned the smash hit adaptation of Roald Dahl’s 1988 novel about a book-mad five-year-old girl with telekinesis, when the involuntary form of facial flatulence rumbles into life during its month-long Edinburgh run that begins tonight, it’s the perfect example of how a slick main stage show can still feel wonderfully rough around the edges.

“For a big musical, the show feels really theatrical,” says Kelly, who wrote the show with composer and Edinburgh Festival Fringe favourite Tim Minchin. “It is polished, but it doesn’t always feel like it, which is great. To do the burp, we talked about loads of different ideas about how to do it and make it feel as though a burp had just happened, but in the end we went for something really simple, which works in big theatres, but which you could do in tiny spaces as well.”

The sort of spaces Kelly is talking about are exactly where the London-born writer began his play-writing career after joining a youth theatre while a teenager working in Sainsbury’s. His first play of note, Debris, was staged at the tiny Theatre 503, situated above a Battersea pub, in 2003. He came to further prominence two years later when After The End was seen at the Traverse Theatre in Edinburgh in a production directed by Roxana Silbert for the Paines Plough Company.

By 2006, Kelly’s BBC Three sit-com, Pulling, co-written with Sharon Horgan, was en route to being nominated for a BAFTA, while his 2009 stage play, Orphans, premiered at the Traverse in a Birmingham Rep production directed by Silbert. The same year saw the National Theatre of Scotland premiere Kelly’s play for children, Our Teacher’s A Troll. With such a relatively left-field back catalogue, being approached by the Royal Shakespeare Company, then led by former director of Glasgow’s Tron Theatre, Michael Boyd, wasn’t what Kelly expected to happen next.

“When the RSC came to me and said they wanted me to do a musical, I said I didn’t have a clue about how to do that,” Kelly remembers. “I think they knew my work from Debris and Our Teacher’s A Troll, and I wrote about three drafts and then Matthew Warchus came on board as director. They looked around exhaustively for a composer, and as soon as I spoke to Matthew about Tim Minchin, I think he knew he was the one.”

Minchin is the Australian-based performer, whose internationally renowned musical comedy show, Darkside, was an Edinburgh hit in 2005, winning him what was then the Perrier Comedy Award for best newcomer. By the time Kelly and Minchin’s take on the story opened in Stratford in 2010, both had been through an extensive development process.

“We did four of these huge two-week workshops,” Kelly remembers, “and it was a lot of work. I don’t really like workshops, to be honest. I find that stuff hard. The first person I want to hear doing something I’ve written is the actor playing the part, but with something this big you just have to get on with it and do it.”

Kelly reckons the entire process took about four years.“Someone said to me at the time that was ten per cent of my life,” he says.

Matilda The Musical looks set to last a lot longer than that. Following its West End transfer, the show opened on Broadway, and went on to win seven Olivier Awards – the most ever won by a musical – and five Tony Awards. It has also toured Canada and Australia prior to its current UK tour. Has such international success changed things for Kelly?

“In some ways it changed things,” he says, “and in some ways it didn’t. I’ve had a show on for the last eight years, which feels strange. As a playwright you tend to have a show on, then it closes and another one goes on, so it is different with Matilda, but after all this time I don’t have a lot to do with it anymore. I don’t think I’m a lot of use to it. I used to go in and maybe give a bit of advice, but at some point you’ve got to step back and let them get on with it.

“How I wanted to work didn’t change. It’s not like this was what I was working towards, meeting famous people and swanning round musical theatre or anything like that. I still write grimy little plays, and always have done, and writing Matilda was no different from writing anything else I’ve done.”

Such a down to earth approach is part of Matilda’s appeal. “There are two things I really like about it,” Kelly says. “The first is Matilda’s inability to accept the status quo, and secondly, she doesn’t whinge about it. A lot of the time in musicals, people say, oh, if only this or that happened, I could have done this. Matilda never really does that. She just gets on with it and sorts things out. I think as well it’s a bit cheeky and a bit naughty as a musical. The great thing about Roald Dahl is he’s rude, and I’m rude as well, and so is Tim, so it all came together because we’re all rude. But apart from anything else, it’s amazing seeing that little girl telling the story, and holding 1,000 people or a couple of thousand people, in the palm of their hand.”

Kelly’s forte charting the adventures of unruly small people has continued with his version of Pinocchio, which he wrote for the National Theatre in London in a production that ran in 2017 and 2018 directed by John Tiffany, formerly of the Traverse and National Theatre of Scotland. In this way, Kelly seems naturally drawn to such fictional trouble-makers.

“Being able to watch someone who is very small overpower someone who is very big, that’s not a bad message,” he says. “I learnt very early on, kids hate things that aren’t fair. If you tell a kid off and you’re wrong, they hate it. I just love the idea that there’s a little girl out there who gets up and sorts things out. We could probably do with a bit of that in the world just now.”

Matilda The Musical, The Playhouse, Edinburgh, tonight-April 27.

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