Kirsty Young on presenting the landmark 75th anniversary Desert Island Discs

IT has reduced some guests to tears and had them share their deepest, darkest thoughts.

Some have become irate, others have squirmed – but most have both charmed and informed, many showing a side the public had never seen.

And along the way we’ve enjoyed countless joyful moments.

Now Desert Island Discs celebrates its 75th anniversary next Sunday, with special castaway David Beckham.

A three-hour celebration will be broadcast to mark the milestone since the first broadcast on January 29, 1942.

When writer Caitlin Moran appears on BBC Radio 4 today it will be on the 3103rd programme, with each Castaway picking the eight tunes, one book and one luxury item with which they’d like to be marooned.

Creator Roy Plomley was the man originally asking the questions. Since then, only three others have quizzed the castaways; Michael Parkinson, Sue Lawley and, for the past decade, Kirsty Young.

East Kilbride-born Kirsty says it has given her countless magical moments – from Tom Jones serenading her to Sir Michael Caine giving her a roast potato recipe.

And Kirsty, who also hosts Saturday’s anniversary special on Radio 4 Extra, told The Sunday Post of her delight at the show’s on-going success.

Three million reckon their week wouldn’t be the same without tuning in; on top of that a couple of million a month catch up via downloads.

“To take over any job from someone who has done it very well for a good, long time is intimidating,” admits Kirsty, 48.

“And Sue Lawley was a hard act to follow.

“But at the time. I was really exhilarated rather than overwhelmed by the challenge.”

A decade on, the figures are at record levels and the download numbers continue to rise.

A small part-time team of just five put the show together, digging into their castaway subject’s life in minute detail.

And Kirsty says that reading all their notes as well as doing in-depth research herself is critical to putting her interviewee at ease. “There’s no substitute for good preparation,” she insists. “You have to have it in your head as you go along to fill in the bits of information that the listener needs,” Kirsty says.

“So each interview is like swotting for a mini exam in someone’s life.

“Once all that’s done I sit down in front of the mic with my Castaway and let the whole exchange be as natural and unpredictable as possible.”

While most people only get washed up on the mythical island once in their lifetime, a select few are invited back again.

Sir David Attenborough is one of just two – comedian and actor Arthur Askey was the other – who has made four appearances.

And Kirsty can fully understand why the broadcasting legend has such an appeal.

“He was so warm and down to earth and incredibly mischievous and funny.

“And Dustin Hoffman was a total delight – very direct and surprisingly a little insecure for someone who has won armfuls of awards. Annie Lennox was admirably un-starry, arriving alone and on foot, munching on sandwiches she’d brought along before we headed into the studio.”

Kirsty cites Tom Hanks “talking incredibly movingly about his childhood” as one of her most memorable moments.

He was on the verge of tears as he spoke about the loneliness of his nomadic childhood, living in 10 different houses with his chef dad in five years.

“People, however high-achieving, have vulnerabilities,” says mum-of-two Kirsty whose husband is Soho House club boss Nick Jones.

“And given that I ask my guests not just about the highs but also the lows of their lives, it’s entirely understandable that sometimes Castaways can be overcome.

“But often those who might be expected to be awkward can pleasantly surprise.

“The Oscar-winning film director of 12 Years A Slave, Steve McQueen – who has a reputation for supposedly being “difficult” – was a total gent and entirely fascinating in every respect.”

Sports stars and prime ministers, movie icons and musical legends are just some of those who’ve shared their most private thoughts.

And they have often turned out to prove very insightful after their death. George Michael had told Kirsty about “self-destructive” elements of his life and how he “spent much of the 15 or 20 years trying to derail my own career because it never suffers”.

But there are happier moments from singers among Kirsty’s Castaway highlights.

“Tom Jones singing to me – well it was to our millions of listeners but I like to pretend it was just to me!” she laughs.

“Interviewing Dawn French, who had made me laugh non-stop since the age of 13, was everything and more than I’d hoped for.

“And getting a great roast potato recipe on air from Sir Michael Caine was great.”