Radio 4’s Desert Island Discs has earned its 75 years on the air by consistently producing revealing interviews with well-known guests like US actor Tom Hanks above.

We asked series producer Cathy Drysdale to explain how the show is made:

- how to book big-name guests - how their lives are researched - what happens during the studio recording - how the programme is edited - what personal qualities you need to work on the series

Cathy reveals the way her team works flexibly to fit in with guests' busy schedules. She also talks about how the producer and presenter Kirsty Young must trust each other explicitly in the studio.

"When I’m looking through the glass and I see Tom Hanks there I am pinching myself. I allow myself five seconds of pinching and that’s it. Then you have to be completely professional.” – Cathy Drysdale

Desert Island Discs airs on Sunday at 11.15. More than 2000 episodes are available on the programme website.