He is arguably one of New Zealand's most successful sportspeople. Yet, until he featured on TV3's 60 Minutes on Sunday, virtually nobody had heard of William Trubridge.
The multiple world champion and the only human to dive completely unassisted to 100m, Trubridge is widely regarded as one of the true greats of the freediving world.
Trubridge and his wife, Brittany, have just been guests of honour at the Doha Tribeca Film Festival in the tiny gulf state of Qatar, where he was premiering a short film, Hectometer.
Hectometer, the only international short film selected for the festival, is dedicated to the cause of the highly endangered Hector's dolphin, something Trubridge is a huge advocate for.
The film festival's red carpet is a long way from his usual environment, deep down in the sea. The film is about his world record-setting dive in the Bahamas earlier this year which came after two earlier failed attempts. On the third attempt he completed the dive in an astonishing 4 minutes and 8 seconds.
"It took a little while to sink in and to catch my breath back again but, once I realised that I had made that mark, then there was a huge sense of relief and exhilaration."
Trubridge was born in England but spent most of his childhood sailing on a yacht around the world with his parents and brother. They eventually reached New Zealand and settled in Hawke's Bay.
"For me, being in the water and snorkelling and swimming was as natural as maybe for other kids it is to play outside in the backyard on the lawn. I guess that's where the beginnings of freediving comes from."
It wasn't until he headed to London on his OE that Trubridge heard about the sport of freediving and went to the Caribbean to learn more. He says he was hooked immediately.
"The beauty of the experience of being underwater without any kind of equipment is completely different to anything that you can experience in the element of air. You're essentially weightless, there's no sound, all the colours are subdued, and the fact that you're holding your breath is, essentially, like a suspension of time."
Freediving, especially to the depths attempted by Trubridge, is perceived as highly dangerous. Not so, says Trubridge. All his dives are planned painstakingly, with multiple safety systems in place.
"In freediving, there's really only one risk, which is blacking out underwater, which is when your oxygen runs out under the water and, so, you basically just faint. If you're by yourself, if there's no one else there, then the only result to that is that you're going to drown."
Trubridge has experienced it himself, the worst in 2006 when he was attempting to set a world record. "I blacked out 12m from the surface on my ascent. I was brought to the surface very quickly by safety divers but it took me a while, maybe 20 seconds, to come round. It was definitely damaging to my sense of confidence."
As well as freediving in the open water, Trubridge also competes in the various pool disciplines of the sport and regularly ranks in the top three in the world. But he insists he has no secret weapon, just a complete dedication to the sport: "There's definitely no super-powers. Physiologically, I'm no different. If there is any difference it's just that I've applied myself to it, and because I have such a passion for the sport maybe I've been able to train harder and longer than other people who are in a similar situation."
His name may be well known and revered in international freediving circles but, in New Zealand up until recently, he has had virtually no profile. He insists that is of no consequence to him.
"I like that it's more of a fringe sport because there isn't as much hype or attention, and I guess I'm kind of lucky in that I can focus more on myself and my performance."
At just 31, Trubridge says he still has many more freediving years ahead of him and many more records to set.
"It's an exciting process of discovery, being in a sport and seeing what the human body is capable of doing."
As well as the short film, Trubridge is also the subject of a feature-length documentary being released this year called Breathe.