Standing on a matte-black stage in the Netherlands in 35degC heat, dressed in dark clothing and singing the last song in his set, Marlon Williams lost consciousness.
The songwriter experienced a total rush, before falling to his knees and waking up a millisecond later.
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"It was like, 'Oh my God, I could have totally just passed out and not been able to finish that song', but I just managed to just claw it back," he told Newshub.
Over the past couple of years, Williams can recall many times he has nearly fainted mid-performance due to over-exertion.
The 27-year-old singer gets to the last song of his set, 'Portrait of a Man', when the combination of sunlight, a black stage or dark clothing gets the better of him.
"I'll be singing that song and pushing those notes out and there's this really dangerous desire to toy with my own consciousness. It's not at all a healthy relationship - it's very intense," he says.
The Silver Scroll-winner says being on stage feels like any sort of chemical-altering substance or activity - "addictive" - and he often struggles to sleep for hours after a gig no matter what he tries.
Williams' adventures showcasing his tunes internationally have taken the Lyttleton singer-songwriter to new frontiers.
Travelling didn't just give him a chance to see the world, but supported his actor.
Superstar actor Bradley Cooper was driving in West Hollywood when he heard Williams' voice on the radio, so bought tickets to see him sing. The Kiwi's talent blew Cooper away.
"I got a call from Bradley a few weeks later, and it was what led to a really fun and exciting project," he said of his part in the acclaimed flick A Star is Born.
"To watch Bradley Cooper with a whole team of financial backers, a whole team of producers, a cast of hundreds... for him to be able to hold on to his vision while playing so many roles and putting on so many hats and dealing with so many people - that was a really inspirational thing to see," he said.
Appearing in a Golden Globe-nominated film may have been far from the imagination of a lad whose interest in music was ignited as a young trumpet player in a corner of New Zealand's South Island.
It was singing that made him think about music all the time - a pastime first ignited by jamming to tunes with his mum in the car.
Williams jumped at the chance to join his school choir because it got him out of class. In practise, he realised he had a stronger grasp on melodies than his peers.
"That was first time I'd ever had more of a handle on something than the other kids, so pretty much from that moment on it was a no-brainer," he says.
He was drawn towards writing his own music, and realised he would be in a better position to express himself if he knew how to play the guitar.
The recording artist taught himself, joined a band in high school and got used to creating his own songs.
The year 2018 has seen him earn a No.1 album, headline shows around the world, announce a 12-date nationwide tour, three Vodafone New Zealand Music Awards (VNZMAs), and a role in a Hollywood blockbuster - making it undoubtedly his best year yet.
Williams' achievements to date are not something he spends time reflecting on, instead taking the lessons from each environment as they come and moving forward.
"I'm not so obsessed with perfection as I used to be."
He has come to understand that there is "no such thing" as a perfect ending point for a song, and learned to accept that a piece of work is only finished because he's stopped doing it.
The hardest part, he says, is letting go: "You could go on forever trying to refine a song."
"To be honest, I've released music that I thought, 'That's not very good', and I've put it out there and sometimes it convinces me otherwise through just being exposed.
"There's something perfect about the exposition of a song to the public that ties it all up and makes all the loose ends tied."
The songwriter isn't totally dissimilar from others his own age figuring out where he fits in life, admitting: "I'm not confident at all; it's a real guessing game."
What makes the 27-year-old stand out beyond his 6ft 3in frame is his commitment to be heard through an authentic sound.
Sharing words derived from a genuine interpretation of his life experiences isn't a happy accident - it's a privilege held close to his soul. If he didn't have it that way, Williams wouldn't make music at all.
He finds a sweet spot in the intersection of folk, country and classic rock 'n' roll - and it's his steady repertoire of soulful and emotive offerings that have enabled him to evolve from his first VNZMA nomination seven years ago.
The temptation to conform to a more generic sound doesn't cross his mind.
"The walls want to come in all the time - but I think I would stop, I just wouldn't be able to do it anymore if it was any other way, you know?
"I'll know when that's happening, I hope, and stop if that's what needs to happen.
"I'll have lived a happy life if I can continue to make the kind of music I want to make, in my own time."
Williams is something of an anomaly in the music world, from the distinctive tones in his melodies to his dishevelled appearance and charmingly awkward demeanour.
His tireless strategy to push the boundaries reflects in his achievements to date. He spent the majority of 2018 travelling the globe, playing festivals and selling out headline tours.
"You come off stage and you're full of adrenaline," he said.
"I find that the more I play, the more shows I do; the more confident I get, the more restless I get, so the more I want to try new things - it's an ever-growing and ever-exciting process."
He will be back in the country early next year to front his very own 12-date showcase, bringing to life the Tūrangawaewae Tour from February 7 to March 3.
Williams will be accompanied by the Auckland Philharmonic Orchestra for his performance at Villa Maria Winery. Each concert will be supported by Emily Fairlight and local icon Don McGlashan.
He says it's the New Zealand shows that cause him the most anxiety.
"It's like going back to your hometown and everyone's going, 'Oh what have you been up to?'
"There's that added sort of familial pressure, but at the same time that pressure is only there because they're the people you want to impress the most."
Being away has given him "an appreciation of being home". He finds true joy in each performance, unfazed by the common factors each expression of his pieces shares.
"The repetition and watching the songs shift around you as you present them to different audiences; you notice different things about them night after night," he explains.
"That's a really lovely thing to come to: the realisation that songs are never static; they don't stay still; they shift according to where you are in relation to them. That's my favourite thing I've learned."
As he follows his instinct as opposed to a five-year plan, Williams places value in working at something that feeds his heart.
"It's got to make you happy, otherwise there's no point," he concludes.
"If it's in a creative field or even if you're an accountant - I know people who enjoy being accountants - but if you don't enjoy it stop... now."