Freediver Kristof Coenen was captivated by the Blue Hole in the Red Sea, sinking to its dark depths on a single breath. But in freediving, pushing to the limit can be fatal. Show more
Discover 11,128,835 listings and 280,099 playable programmes from the BBC
Freediver Kristof Coenen was captivated by the Blue Hole in the Red Sea, sinking to its dark depths on a single breath. But in freediving, pushing to the limit can be fatal. Show more