British director and photographer Ian Derry talks about his profile of Finnish freediver Johanna Nordblad, who holds the world record for a 50-meter dive under ice, after finding the sport during recovery from a downhill biking accident that almost took her leg:

“I became aware of Johanna from her sister who is a photographer. I liked her story—to have such a terrible injury and to overcome it in the most extreme way.

“Once I had met her and gone to the location—which at that point was -24C—I knew I had to make the film. The environment and the silence there is something I will never forget.

“I dived under the ice to get a perspective on it and it was literally breath taking. What she does is so close to the edge, but she does it in such a comfortable way.”