Kirsty Young's guest is filmmaker and criminologist, Roger Graef.

Pioneering in his chosen subjects and style, for the past fifty years he has shone a spotlight on hitherto hidden areas of society and influenced the entire genre of modern day documentary making. His films on key institutions like the Police have not just helped change attitudes but policy too.

A New Yorker and Harvard graduate, he first came to Britain to study Shakespeare: his London debut as a theatre director was a Tennessee Williams' play. He soon realised that the drama and storylines of real life were where his heart and talents lay.

He says, "What I want on my gravestone is 'Here Lies Roger Graef - he made a difference ...' and people are telling me that I have. But I don't think about it because there's so much left to do."

Producer: Cathy Drysdale.

Kirsty Young interviews the composer Debbie Wiseman.

Her work is wide ranging, but her talents are most often employed in crafting lyrical, melodic scores for film and TV. Her credits include Land Girls, Judge John Deed, Haunted and Father Brown. Now a visiting Professor at the Royal College of Music, her unlikely introduction to the piano came at the age of 8 when she found a bashed up old instrument sitting in the corner of a hotel dining room.

Producer: Isabel Sargent.

Kirsty Young's castaway this week is the historian, gardener and diarist Sir Roy Strong.

He stormed the establishment in the 1960s - a proto-meritocrat, in possession of a sharp mind, fizzing ambition and a brown velvet frock coat.

An avowedly unhappy and clever child he turned first to history and then art for stimulation and solace, setting down a template for a working life that would lead him to be the youngest ever director of the National Portrait Gallery and, later, to run the The Victoria and Albert Museum. Such early success left him with a fundamental problem - having fulfilled his wildest dreams by the age of 38 - what was he to do with the rest of his life? He would go on to publish his diaries and together with his wife Julia, created a garden at his home in Herefordshire, the Laskett.

Producer: Cathy Drysdale.

Kirsty Young's castaway this week is the writer Sally Wainwright.

TV is her chosen medium and Last Tango In Halifax, Happy Valley or Scott & Bailey are watched by millions of viewers. Her ear for dialogue and talent for story-telling place her among the cream of small screen dramatists: she majors in whip-smart phrasing and plot lines that twist the innards with their tension, but never strain plausibility.

Her passion for every day drama was honed at her mother's knee: in the 60's and 70's as Mrs. Wainwright watched Coronation Street, young Sally tuned in too, developing an affinity with the power of the portrayal of language as it is spoken and life as it is lived. She would later go on to write for the show.

She says, "When I was seven I started writing down the things people said - it was something I just had to do. I think I was born with it - it's like being able to draw or paint."

Producer: Cathy Drysdale.

Kirsty Young's castaway this week is the conductor, Marin Alsop.

Music Director of both The Baltimore Symphony and The Sao Paulo State Symphony Orchestra, she is a maestro with a mission: music, she believes, is a powerful vehicle for social change.

She had the good fortune to be brought up in "a household that exuded possibility" and was filled with music - both her parents played professionally. She took up the piano aged two, swapped to the violin at 6 and then aged 9, saw Leonard Bernstein at work and made the decision that conducting would be her career. Much later she would go on to be mentored by the man who inspired her.

It bores her when interviewers ask why there aren't more women conductors - nonetheless her capacity to maximise the few opportunities she was given as a young woman making her way in an exclusively mans' world gives one a flavour of her indomitability. Her day-to-day job after all is working out how to convince 100 experts to do what she wants.

She says, "maybe it's being an only child: you want to bring people together and create this big family feeling, I don't know what it is but I always gravitated towards organising."

Producer: Cathy Drysdale

Kirsty Young's castaway is the artist and director Steve McQueen.

These days his talents are well recognized - his art has won The Turner Prize and his most recent movie, "12 Years A Slave" scooped an Academy Award, a Bafta and a Golden Globe. He wasn't always as lauded: at school in West London he was "shoved to one side" in the belief that the best he could hope for was to earn a living as a manual labourer. Instead he portrays the extremes of what human beings put themselves and others through. Expression is where his heart lies - he describes it as "dancing with ghosts".

Along with reaching the top of two professions he has also managed to please the diverging demands of his parents - his father wanted him to get a trade, his mother urged him to do what he wanted.

He says, "I want to make films that are essential. We're all going to die and we haven't got a lot of time on this planet. Life goes very quickly, so we might as well make films people will go to see because they need it or want it."

Producer: Cathy Drysdale.

The writer Malcolm Gladwell is interviewed by Kirsty Young for Desert Island Discs.

Always concise, frequently counterintuitive and unexpectedly beguiling, his work orders the world in a way that gives fresh insights into human behaviour.

He believes that a knowledge of people's backgrounds is necessary to understanding their success; his own achievements may presumably then be attributed, not just to his keen mind and polished prose, but also to his parents - an English mathematician and a Jamaican psychotherapist.

He says, "I am the bird attached to the top of a very large beast, pecking away and eating the gnats.... I am someone who draws inspiration from the brilliance of others and repackages it ... I am a populariser, a simplifier and a synthesizer."

Producer: Sarah Taylor.

Guy Garvey, musician and frontman of Elbow, is interviewed by Kirsty Young for Desert island Discs.

Front man of the group "Elbow" his voice and lyrics have helped the band win pretty much every music prize going ... headlining Glastonbury too, and playing at the closing ceremony of the London Olympics. Yet his image is that of an everyday, low key, unassuming bloke ... except that he isn't, he's penning and performing songs filled with intimacy, optimism and lyricism, that strike a chord with millions of fans.

For a long while his devotees were well versed in the art of delayed gratification - Elbow's debut album was released 11 years after the band members first made music together.

He writes his songs in his journal and has been keeping a diary since he was 14. Maybe it was the peace and calm of the blank page that first appealed - one of 7 kids he says he was brought up "in a house full of women that were singing, shouting, arguing, fighting over the bathroom. I'm ruined by these women, spoilt rotten".

Fellow of both the Royal Academy of Engineering and the Royal Society, Dame Wendy fought long and hard to prove that her type of web science was highly significant and here to stay. If algebraic topology and open hypermedia systems really aren't your thing, Dame Wendy is also in demand as a brilliant communicator on, what can seem to outsiders to be, impenetrable topics.

Her parents were from humble beginnings and it was clear from the get-go that their first born had a budding flair for numbers: aged six she was charged with teaching a group of schoolmates maths. The first in her family to go to University she rejected Cambridge, judging it "too stuffy".

She says, "I get too excited about stuff. I love my life and am passionate about web science, women in science and shopping".

Producer: Cathy Drysdale.

Doug Allan is Kirsty's castaway this week.

A trained biologist he first made a living diving into the icy rivers of Scotland searching among the mussel-beds for pearls; a useful early lesson in patience and coping with the cold. His subsequent dedication to a working life in the wilderness has bagged him a slew of Baftas and Emmys but there's also been an emotional toll - he's coped with periods of depression and is twice divorced.

He says, "Big animals are my passion. I particularly love working with large mammals because they're intelligent and you can develop a relationship with them"

And he's at his happiest at -18 degrees centigrade!