The actor with Down's syndrome tackling Dickens

Daniel Laurie (second from right) with fellow cast members of R4's Barnaby Rudge

An actor with Down's syndrome is to play the title role in BBC Radio 4's new classic serial, Barnaby Rudge. Although his non-standard speech might be an extra challenge for the listener, the producer feels it shouldn't happen any other way.

"Basically having Down's syndrome is kinda cool. To me it's absolutely cool. I so yeah, that's how I've got Down's syndrome... and you absolutely crack me up." Daniel Laurie is 19 and is a dream interviewee. He's very funny, charming and with each question comes an unexpected and interesting response.

He plays Barnaby Rudge in a new radio adaptation of one of Charles Dickens's lesser-known works. Rudge is an "idiot" as the language of the time would have it. Today we might say he has a learning disability.

"People get hung, tragic death, and it's involved to the story," says Daniel on Dickens's historical novel, which is set in London against the backdrop of the Gordon riots of 1780. We hear Barnaby with Grip, his ever-present and outspoken pet bird. "Grip is a raven for me, back in the days of the BBC. It's got the greatest actress who plays this Grip, it was Joanna. And she's really, really great, she's outstanding to me."

Daniel's pattern of speech will be very recognisable to people who have friends and family with Down's syndrome. Jeremy Mortimer - who has a nephew with the condition - produced and directed the radio adaptation and was responsible for the casting. "It feels to me truer to Dickens's original intentions to have somebody we recognise. I think it makes it truer than having someone be humorous and play the part of a simpleton. I don't relate to that in any way, so I thought it was a more honest approach really."

In the book, the visuals betray that Barnaby Rudge has a learning disability:

"He was about three-and-twenty years old, and though rather spare, of a fair height and strong make... The fluttered and confused disposition of all the motley scraps that formed his dress, bespoke, in a scarcely less degree than his eager and unsettled manner, the disorder of his mind, and by a grotesque contrast set off and heightened the more impressive wildness of his face."

An illustration of Barnaby Rudge and his raven Grip

On radio, listeners are introduced to the fact suddenly, when Daniel speaks his first lines.

"I've said nothing in the opening announcement that [a person with Down's syndrome, is playing it] so there's no way of preparing the audience for it," says Mortimer. "I think some listeners may find it a bit hard to immediately get to grips with but I hope they stay with it."

Mortimer auditioned candidates for the role by telephone, so he could experience their voices only. He says Daniel had good pace, variety of tone and totally understood the character: "Danny's mum Jane was an important part of the process, she was in the studio with Daniel managing scripts and there to help when he needed it."

Jane Grantham, Daniel's mother, talks down the significance of her role. In her words, she was there to just "pace him" through the 10-hour days of recording the serial and describes him as independent and ambitious. "The first day we got to the huge BBC building, which we'd never been to before, he actually thought I was going to drop him off on the corner and let him walk in on his own," she says. "He was furious that I decided to come in with him. He probably still hasn't recovered from that. He's got no idea why every time he turns around, his mother is still there."

Though acting is his passion, Daniel's efforts are currently focused on re-sitting Maths and English GCSEs, and he is working towards training to be a nursery school assistant. He has done work experience at a local Montessori. "Kids just gravitate towards him," says Grantham. "He's very patient and kind and he'd happily read the same story again and again and happily play his guitar and football. He'd be the perfect assistant."

In the serial, much to the distress of his mother, Barnaby goes missing and later re-emerges with the rioters. He is put in prison for his part in the riots and goes to court. "The law at the time didn't make any accommodation for people who didn't know what they were doing. You were either innocent or guilty," says Mortimer.

"I think Dickens is putting Barnaby in this position, so that people can say well actually all of us are a bit like that, we're all a bit naive, we get swept into things, we don't quite understand what they are. We just know that Barnaby is very vulnerable and all he has with him is his pet raven, Grip, who he's very fond of. It's a very good way of bringing us into the human story."

Daniel has had plenty of acting experience at a drama group he attends in his home in south-west London - but is working with three hours' worth of scripts in a busy studio a major challenge? Not according to Daniel.

"Sometimes I just read them but all the time I don't," he says. "My mother told me that I've got an elephant-sized brain because I did an elephant's face for her.

"Acting is a job I really want because I get a lot of pay and I'm doing this because I want to visit my brother Jake who lives in Hong Kong. I want more money to see him and go in first class!"

Barnaby Rudge is broadcast in three episodes on BBC Radio 4 - episode one is on Sunday 25 May at 15:00 BST - or listen on BBC iPlayer

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