Martin Henderson laughs when it's suggested he's Everest's most qualified cast member.
After all, he's the only New Zealander playing a New Zealander in the acclaimed alpine disaster epic.
The Hollywood-based expatriate plays Andy "Harold" Harris, a guide for Rob Hall's company, who was one of eight who died on the mountain in May 1996 when climbing parties were caught in a storm.
Auckland-raised Henderson isn't a stranger to the outdoors or high altitudes, either. The onetime Shortland Street star had been to the Himalayan foothills before the Everest shoot took him there.
But his most hair-raising great outdoors story involves being chased by a rhino in the Nepalese jungle.
"I actually thought it was going to be my last breath," he laughs down the line from somewhere in Georgia where he is playing a vet in family movie Miracles from Heaven opposite Jennifer Garner.
"I thought this is going to read so bad in a New Zealand article. 'Whatever happened to Stuart Neilson? Oh he got killed by a rhino'. Kind of exotic and pathetic at the same time."
It was a decade or more ago that Henderson heard about the project, which would undergo a stop-start path and many script overhauls before eventually going into production.
"I remember in the first version I was interested in Rob Hall's character. As a Kiwi, that was 'Oh man, that is a character I would love to play'."
But the project foundered for many years until it was resurrected with Christian Bale and Hugh Jackman in the frame for the Rob Hall role. The part eventually went to rising Australian star Jason Clarke.
Henderson and Clarke share an agent, so he was able to keep tabs on the movie. He read for the role of New Zealand mountaineer Guy Cotter (played in the movie by Sam Worthington; the real Cotter became the mountain safety manager on the shoot).
Everest stars feature on the cover of this week's TimeOut:
Being cast as Harris was even better, says Henderson. He didn't mind too much that he wasn't the lead. After all, Clarke's a mate.
To prepare for the movie they went climbing together in the Southern Alps as well as knocking off Scotland's Ben Nevis.
"If he wasn't a buddy I would maybe feel a lot more disappointed but I just love Jason as a friend and as an actor.
"For me I think he was perfect for the role. Obviously my Rob Hall would have been very very different. I feel type-wise, he was probably more accurate. The character was way better served with the way the casting went down."
Harris may be a supporting role but it's pivotal to telling the story of what went wrong on the mountain.
It was Harris' first ascent of Everest. He summited before disappearing in the chaos as the storm hit.
As a guide it was Harris' job to look after the slower climbers in the group led by Hall. There are conflicting accounts of what happened to him but there is conjecture, in Jon Krakauer's Into Thin Air account of the disaster, that he may have lost his life while trying to ascend again to help Hall and another climber who also died.
"In the final cut you don't know how much of the movie you are going to end up in, when you have a giant cast like that. But the fact that he really is a presence and his memory is honoured - and particularly the heroic nature of the character, I felt really happy about."
Henderson met Harris' family before the shoot.
At the time of the tragedy, they had got word from Nepal that Harris was alive and well, only to be told later he was missing.
"They were gracious enough to spend a lot of time with me and share anecdotes about that period in his life."
Henderson thinks it's possible the family would have been happy that a high-profile New Zealander playing Harris.
"It would be nice to think so, rather than an American actor or an Australian actor. It was a connection for them that I was someone from New Zealand.
"Then again, I think the whole film should have been filled with Kiwis in those roles," he laughs.
"I just sincerely hope my involvement in any way was some kind of comfort - or there was something nice about honouring him as a Kiwi.
"In all the research I did, I could not find anybody who did not say marvellous things about the man. He was so well respected and loved."
Everest is a film with an ensemble cast of considerable international star wattage.
It includes Josh Brolin as Texan climber Beck Weathers, Robin Wright as his wife Peach, Emily Watson as Hall's base camp manager Helen Wilton and Keira Knightley as Hall's wife, Jan Arnold.
As well as acting, Henderson became the shoot's unofficial accent coach.
"I was the consultant, yes. I strongly suspect that was the only reason Jason had me on his training expeditions - so he could start to hone his ear. He did a good job and it's not easy for an Aussie.
"They can do it as a parody - they are good at taking the piss out of us. But I think he did a really nice job. It's a tough accent. It's difficult for actors who are not Kiwis. It's actually reassuring to see people struggling to do our accent instead of us constantly trying to emulate British or American accents, which we are always asked to do."
The outdoor shoot in the Italian Alps during winter came with its own risks. Henderson remembers a mountainside set that was meant to emulate the steep slopes of Everest's Camp Three.
When a storm struck, Cotter soon ordered the production off the mountain. A couple of hours later, an avalanche buried the set.
Still, Henderson reckons those calculated risks were worth it, judging by the finished result.
"I think the movie is really good and not just as an action-tragedy-adventure thing. I really felt, watching it, that it moved me so much and it's rare that a big action movie does those things.
"Anyone whose lives were lost in the tragedy, we felt a deep sense of responsibility to honour those people authentically and pay tribute to who they were.
"It's a New Zealand story and it's lovely to be part of that."
Dr Henderson, I presume
He's gone from ambulance medic Stuart Neilson in the early days of Shortland Street to a jungle doctor in short-lived American medical series Off the Map. Now Henderson is putting on the white coat again as he joins the cast of long-running hospital drama Grey's Anatomy.
Henderson says he is looking forward to finally working on something that shoots where he lives in Los Angeles.
As to why he's been cast in yet another medical role, he's not quite sure, though like Off the Map, Grey's Anatomy was created by US television powerhouse Shonda Rhimes.
"Its kind of a nice full circle," he says about being back on another clinical drama. "Well half-circle. I'm not that old."
And he cannot shed light on his role yet.
"I don't even know who my character is in Grey's.
"I could be a tyrannical egomaniac surgeon or I could have a nice bedside manner."
Who: Martin Henderson as Andy Harris and Jason Clarke as Rob Hall in Everest
When and where: At cinemas from September 17