Benedict Cumberbatch climbs sea cliffs and survives frozen waterfalls in Scotland in a new episode of the series “Running Wild with Bear Grylls the Challenge”.

It wasn’t nice, especially at first,” Cumberbatch joked after successfully descending a dangerous-looking hillside.

The English actor explained that he agreed to appear in the adventure and survival series because he wanted to learn more about resilience. “I feel like I’m in touch with my grandfather,” he added. “I wish he was around. It would be under the water, instead of on the water, but, yeah, there’s definitely an issue here,” he noted.

The actor’s late grandfather, Henry Cumberbatch, was a submarine officer in both World Wars.

In the National Geographic series “Running Wild with Bear Grylls the Challenge” by Edward Michael “Bear” Grylls and Delbert Supman, guests are tested both physically and mentally beyond their limits (hanging off a cliff, traversing a frozen waterfall) and trials help them conquer their fears.