Kirsty Young's castaway is the adventurer Bear Grylls.

His first career was with the SAS, but he was forced to leave after a parachute jump went wrong and he broke his back in three places. As he recuperated, he rekindled his childhood ambition of climbing Mount Everest - he went on to become the youngest Briton to reach its summit. His TV series, Born Survivor, has a global audience of more than a billion people who regularly watch him eating the apparently indigestible and risking his life by pitting himself against nature. Married with three young sons, he says: "The unresolved struggle in my life is the fact that I have a job that has an element of danger to it and at the same time I have a gorgeous family - three young boys that are the pride of my life."

Producer: Leanne Buckle.