Ben makes an unprecedented third visit to see his old friends Bill and Bob, elderly twins living in the canyons of Utah. During his previous stays, Ben quickly learned that nothing was quite as it seemed with his eccentric hosts. His home for the week was a cave. He discovered that the brothers were preppers, with several years' worth of supplies hidden in their caves. He also learned that Bob had suffered a stroke and on this visit is saddened to see that his condition has not improved with age. Ben also observes that their paranoia about the outside world has grown. He reassures them that life away from their caves might not be 
as they perceive. 

Ben returns to the enchanting Suffolk countryside and a hidden woodland to reunite with the extraordinary Will Lord, a true British caveman. In their last encounter, Ben fully immersed himself in Will's 'Stone Age' lifestyle, helping to build a primitive home and learning survival skills like fire-starting and coracle boating. He also spent quality time with Will and his father, renowned flint-knappers. Now, nearly three years later, Ben is back to explore how Will's prehistoric dream has evolved and how his family and friends have embraced this unique passion for ancient living.