Imagine a plunge into a dark and all-consuming ocean, aided only by a single breath. For some, that sort of image lingers on the edge of nightmares, but for documentarian Laura McGann, it evokes something more inspiring: the subject of her latest storytelling endeavor. “Looking at these people behaving more like dolphins and seals than human beings, with nothing attached to them, just their wetsuit or bikini, and the light — it was incredible,” the director recalls of her first interaction with free diving. “I was so curious about these athletes and why they chose this sport.”

With The Deepest Breath, McGann goes deep into the world of competitive free diving — a fiercely intense sport that sends an athlete hundreds of vertical feet down into the sea — through the eyes of two of the community’s most beloved members, Italian competitor Alessia Zecchini and Irish safety diver Stephen Keenan. “I tried to tell Alessia and Stephen’s story in such a way that you’re very much in the moment,” says McGann. “You hear their voices and you go on their journeys.”

The Deepest Breath follows Zecchini and Keenan’s ascent within the sport as they develop an unbreakable bond and chase their seemingly impossible dreams. Charting their relationship with each other and with free diving, McGann examines the emotional drive behind such an extreme sport, and the mind-bending physical and mental challenges that divers endure to thrive in open waters. “It’s really all about controlling your own thoughts,” says the filmmaker. “You can’t have negative thoughts or fear. So it’s a mental sport, and it’s an extremely physical sport. But then you’ve got this other element, which is going into what feels and looks like space. Zero gravity, completely dark. We really tried to capture all of those elements in this film.” 

Queue breaks down the feats of The Deepest Breath, by the numbers.