If you’ve got that life skill of swimming under your belt, then you probably remember where you learnt it. It could have been a public pool close to your home, or perhaps even a sea on holiday, either being taught at school or by family members. One thing is for sure, that one of the activities that came with it was holding your breath.

Filling your lungs with air ‘til it feels like they’re ready to burst as your head submerges below the water line, trying to hold it as long as you can, and more importantly, trying to hold it in longer than family and friends.

Who would have thought that doing so has gone on to become an extreme sport, attracting thrill-seekers from around the globe to participate in free-diving.

Laura McGann’s documentary plunges head first into the dangerous world of free-diving, showcasing a dedication by all those involved at it, taking risks that have proved fatal to many.

From an early age, Italian Alessia Zecchini had a fascination with water. At the age of 13, she completed her first course in apnea, which concentrates on the ability to hold your breath. It’s an ability she’s put to good use both in the pool and sea, going on to become one of the world’s best freedivers.

This is a sport that sees individuals follow a guide rope into the sea for as deep as they can go, all on one single breath.

Someone else who became enamoured with the sport is Irishman Stephen Keenan, a young man who had itchy feet, and found himself having adventures all around the world. It was on one trip that he discovered freediving, and fell in love with it. But having struggled on a number of dives, he become attracted to the role of the safety diver, who would be on hand during these big events, to do their best at keeping those divers who run into trouble at these depths alive.

It was probably fate then that brought these two together, sharing their passion for diving as they did, with Stephen becoming part of the safety team for Alessia’s record-breaking dives.

But as the statistic point out, it doesn’t matter how safe your dive seemingly is, it can never guarantee something going badly wrong.

If you’re not familiar with the sport of freediving, McGann’s documentary serves as a fascinating introduction. But it’s more than that.

The Deepest Breath is undeniably a love story. On the surface there’s the relationship that develops between Alessia and Stephen, but dive a little deeper and the one true love that all those participating in this film share is that for the sea.

And it’s this infinity that many have with it that McGann captures so well, despite the many risks that come with it. Take lung squeeze for instance, which sounds as nasty as it is, when your lungs can’t take the pressure anymore reaching certain depths. With a death rate of roughly 1 in 500 free dives recreationally, it’s not defined as an extreme sport for nothing.

The film itself is a bit of a balancing act for McGann, as she divides the film between a blossoming relationship and the world of freediving itself. It’s something the director doesn’t quite get right, as she focuses too heavily on the romance, and less on the competitive side. For instance, the competitive relationship Alessia had with her Japanese adversary certainly spices things up, and it would have been interesting to see that side developed further here.

There’s so much back story, to the point where you can’t help but think “we get it, these two are going to meet and all in love, get on with it already”. McGann could have got there a lot quicker, without spending so much time going through the family album, and snippets of footage on their travels.

But McGann is keen to focus purely on this relationship, perhaps due to the fact it has a bigger pay off emotionally. The director throughout uses language from her contributors in a certain way, that hints that a happy ending may not be on the cards, which is likely to hold an audience’s attention.

There is one scene however, that doesn’t quite sit right, regarding timings for a particular dive that are literally a matter of seconds, but really do make a huge difference; this discrepancy is highlighted in the documentary, but never actually questioned, which is disappointing considering the consequences of these actions.

By the end of it though, it’s not difficult to see how this love affair for both the sport and sea can affect so many, with McGann taking us on this journey through the depths, with some stunning cinematography, that is likely to take your breath away, but thankfully in the safety of your own home.