Actor Joseph Fiennes and his cousin, renowned explorer Sir Ranulph Fiennes, are the focus of a new two-part National Geographic documentary titled "Fiennes Return to the Wild." The documentary follows their expedition to revisit British Columbia in Canada, where Sir Ranulph first led a pioneering expedition by river in 1971.

During their journey, the cousins share heartfelt moments and reflect on Sir Ranulph's storied career and current challenges, including his battle with Parkinson’s disease. Sir Ranulph, recognized by The Guinness Book of World Records as “the world’s greatest living explorer,” shares personal anecdotes and reminisces about his adventurous past. The 80-year-old explorer and Joseph, aged 53, also explore the emotional and physical tolls of aging and illness.

The documentary highlights Sir Ranulph’s achievements, including his daring expeditions to the North and South Poles and his successful charity efforts, inspired by a conversation with Prince Charles. Despite suffering a heart attack in 2003 and later being diagnosed with Parkinson’s, Sir Ranulph has continued to push his physical limits, completing grueling events like the Marathon des Sables.

Joseph, an accomplished actor known for roles in "Shakespeare In Love" and "The Handmaid’s Tale," expresses profound admiration for his cousin. The film captures touching moments between the two, illustrating their deep familial bond and mutual respect.

"Fiennes Return to the Wild" premieres on Sunday, May 26, at 8 pm on National Geographic.