was left almost lost for words and in tears by an incredible connection to his grandfather while filming a gruelling survival TV series.
Running Wild with has boasted several huge names over the years, from to , and .
Doctor Strange star Benedict was one of the latest to appear, exploring the coast of the Isle of Skye in Scotland.
The 46-year-old’s grandfather, Henry Carlton Cumberbatch, was a submarine officer during the First and the Second World War.
Henry retired from the Royal Navy in 1945 and died at the age of 65 in January 1966.
While Benedict never met his paternal grandfather, during the TV programme that he made with Bear, 49, he felt deeply connected to his ancestor when he came across an actual Royal navy nuclear submarine in the water.
It wasn’t there by coincidence, as Bear had ‘called in a favour’ so that Benedict could lay his eyes on a vessel like one that his submarining grandfather would have gone underwater in during the war.
In a clip shared by adventurer Beat on social media, he tells Benedict that he has a little surprise in store for him to end their journey.
‘Are you ready for this?’ he asks, as Benedict tells him: ‘No, lead the way.’
The boat turns in the water, as Bear instructs the Oscar nominee to look over at a submarine in the water ahead.
‘Oh wow,’ Benedict says in awe, as his host tells him: ‘I did call in a favour with the British Royal Navy to ask would they have a nuclear submarine.’
He then finds out that they’re going to be ‘one of the few civilians ever to get to go on’.
Speaking to the camera Benedict emphasises how moved he feels to have this unexpected connection with his grandfather on the show.
‘My grandfather’s been playing in my mind quite a bit over the past couple of days and it felt like a very immediate connection to him, and to see it was just an oh my god shock moment,’ he says.
Wiping away tears, he says: ‘Amazing. I’m so moved, I’m so moved by it.’
On Twitter, Bear wrote: ‘A powerful moment of raw emotion for Benedict Cumberbatch as we ended our @RunningWildwBG journey… Benedict’s grandfather had commanded a submarine in WW2 and I felt proud to be able to involve the @RoyalNavy & @RoyalMarines to help us end the adventure… thank you so much!….’
Several of his followers expressed how moved they were by the footage, with one writing: ‘it was very touching.’
Running Wild with Bear Grylls airs on National Geographic.
