He's been paid handsomely to throw punches at both Tom Cruise and Bruce Willis without even flinching. But what is the one thing that makes this muscle-bound, towering Aussie dude tremble in his boots?
"Doing this interview is scary," confesses WAAPA graduate Jai Courtney. "This is my first junket. Full stop. It's very intimidating."
For a bloke who's fast forging an image as Hollywood's latest go-to tough guy - first honing his skills back home as Varro, sparring with Andy Whitfield's Spartacus - he's unafraid to reveal that his dramatic inspiration came from his big sister who forced him to do dress-up and act out plays.
"I was just an outgoing kid who liked dressing up a bit too much and wound up on the stage," grins Courtney, 27, who grew up in the Sydney suburb, Cherrybrook, the son of electrician Chris and teacher Karen.
Courtney played rugby league at club level in Sydney as a teenager before concentrating on acting.
Attending local drama groups after school, he later won a place at WAAPA.
"I sucked at ballet but we had a dance element there and you can apply it to anything whether it's a fight or a dance. You understand where your balance is and learning the moves and avoiding injury to yourself and others."
Courtney was a member of the strong class of 2007, which also included his good friend, Jimi Bani. Both young actors were profiled together in _The West Australian _ after landing plum roles in world-premiere plays at the 2008 Perth International Arts Festival. Bani, who has since gone on to star in The Straits and Mabo, played the title role in Jandamarra and Courtney played brooding abattoir worker "Boner" McPharlin in the adaptation of Tim Winton's The Turning.
Courtney said at the time he had no illusion about this early good break after being cast well before he graduated.
"It is very exciting to be given the opportunity to do a professional production so soon after graduation," he said. "It is pretty good to be paid for doing something you love so much."
It was also while auditioning at WAAPA that he met his long-time love, actress Gemma Pranita.
Once smitten, Courtney would grow used to being the lesser-known half of the couple as his Thai-born girlfriend became famous as Neighbours' Jade Mitchell.
But with Courtney now landing roles in Jack Reacher, A Good Day To Die Hard 5 and as the leader of a gargoyle army in horror flick I, Frankenstein, the tables have turned.
Pranita said her final farewell to Ramsay Street and moved to Los Angeles, where her boyfriend is about to become one of Hollywood's most visible new stars.
However, working with Tom Cruise on Jack Reacher was certainly a baptism of fire for Courtney, especially during brutal fight scenes where he goes fist-to-fist with the world's most famous actor.
"You've got to come really prepared but, look, you're human, obviously those things happen but you hope it's not a big right hook and you're not knocking out teeth," says Courtney .
He plays a sniper-for-hire named Charlie in this bloody action thriller whose premiere was actually cancelled out of respect to a nation in mourning after the brutal mass shooting of primary schoolchildren in Newtown, Connecticut.
"But Tom's pretty hard and can hang with it. He's certainly no pussy, that's for sure."
In researching his role, Courtney spent time with a former NAVY Seal. "I really wanted to know what it was like to kill someone," he says.
"This guy had done it many, many times in the line of duty and he said he felt much more emotionally damaged walking upon an animal that he'd hunted and killed but when it came to being in the armed forces, that was the job: it was like him or me.
"It wasn't about an emotional connection to that human being but simply about putting a target on their back and taking them out.
"You had to detach in order to be good at your job and to survive."
Courtney himself doesn't know if he'd be capable of killing.
"But primal instinct is a pretty powerful thing," he muses.
"It depends. You've gotta look at what's at stake I guess. I hate to think that people go and senselessly murder others.
"But it's an interesting thing, the human condition. I think we're all capable of extraordinary things."
With Courtney's star well and truly on the rise, he is now looking to move permanently to Hollywood.
"I've been living out of a suitcase for the past few years," he says. "Sometimes that's fun and sometimes it's a nightmare.
"I'm in an interesting transition period now where I'm basically looking to move here permanently.
"I basically packed up a whole apartment I had and it's stashed in my old bedroom at my parents' place, and it's now time to go home and sell all that old crap and make the move. It's definitely the next step."
Jack Reacher is now screening.